In the parts of Maryland that require an emissions test, if your car is OBD-II equipped, they don't even run an actual test, but just read the code/status information from the OBD-II port. Or at least that's the way it used to be
The OBDII system is emissions testing built right into the car. That means your car is being tested every time you use it, and if the light comes on, that means that it failed part of the test. Some areas have a monitored system, others rely on the owners to have their cars serviced.
Also in Maryland, it used to be that if your vehicle failed the emissions test, you could get a waiver if you could show that you spent $450(?) on emissions related work to try and correct the problem. My '87 BMW was notorious for just barely failing the NOx part of the test. So I would always wait until I failed the test to have work done that might affect emissions
That was pre-OBDII and may have been a broken car, and may not have. the dyno-tests were capable of a lot of false failures, but like any of the programs they were a compromise that had more successes than failures. High Nox can be caused by poor (insufficient) EGR flow as well as a weak catalyst, or a system that is too lean to allow the catalyst to function correctly. It's also possible that it was a false fail that had the vehicle tested at just the right speed where a particular car simply didn't work efficiently. That's why OBDII is better BTW.
The wiki link does a pretty good job of explaining when it was required, it actually "began" in the early 90's because we had a nightmare on or hands with over twenty adapters for our scan tools to try and connect up to some of the cars. In some cases, manufacturers didn't even have any scan data until 95, just before OBDII. When OBDII came out in '96, they only had the minimum number of required data pids. (GM had way more than that in 1980)
Today full diagnostic capabilities on some cars still requires the use of connectors other than the 16 pin ALDL. Keep in mind OBDII is an emissions system, and wasn't actually built as a diagnostics platform.
I bought my Tech II in 2001, it was the first O.E. tool that I stepped up and purchased. The difference in its capabilities as compared to the Snap-On MT2500 (Red Brick), and my Vetronix Master Tech at that time was eye opening. My Snap-On had been purchased some seven years before that and had been upgraded once, and with all of the updates probably represented some $15,000. (That has since doubled today with the change to the Solus, and the continuing upgrades). The Master tech was a $13,000 purchase in 1999, and with updates and getting the Toyota (08), Honda(04), and Nissan (08) factory upgrades for it represents some $20,000. Upon seeing what the O.E. tools could do as compared to what the aftermarket versions could we added the Ford IDS to our list, and Chryslers DRBIII, and StarScan for a grand total today that is over $100,000 for all of them and that total invested continues to climb each year.
My Tech II has grown to represent over $20,000 invested all by itself, but you cannot do the job correctly without it on the GM vehicles. Then one day the cloned tools started showing up on E-bay. People could purchase a current year cloned Tech II ($1500) for just about what the yearly update was costing me ($1395). At first we didn't know what they were, and thought they could be stolen, or subject of a business closing, until we realized that they had current software and that didn't make any sense to sell it that cheap. Then the word came out that these were clones, counterfeits, and we found that out by some of the tools breaking and the purchaser sending it in to have it repaired, only to have Bosch (Vetronix) confiscate the tool.
The article linked is only a drop in the bucket as to how many of these that are out there, but its a start. Try and imagine how it felt to see someone spend $1500, and get to pull even tool wise where I had over $20,000 invested. The one thing that they are failing to do here is recover the counterfeit tools, and then let the purchasers go back after the seller. Part of the solution for the tool counter-fitting is the switch to the laptop based tools that we only get a license to use the software for a limited period of time. At least with the Tech II purchase, as well as the NGS, DRBIII, StarScan, they may be limited by model and year, but they continue to work even if there are no more updates. The laptop based tools turn off when their license expires.
The most common reason for a Check Engine light is a faulty oxygen sensor, says Kristin Brocoff, director of corporate communications for CarMD.com,
Gee, today the most common cause for a check engine light is now an O2 sensor? Didn't it used to be the gas cap? The reality is that there isn't one single likely cause, and every even needs to be diagnosed and repaired correctly as an individual occurrance. That's the fatal flaw with CarMD's approach. It sells their $100 toy tool, and like a chinese auction some people do get lucky with it, but most do not. Some keep changing parts until they have spent a small fortune and still haven't repaired the car only to find out we would have been far less expensive of a choice.
which sells an automotive diagnostic tool and provides repair information. Sometimes, even before an oxygen sensor fails, it becomes "lazy," not properly regulating the gas/air mixture, and that will cause a smog check failure, Mazor says.
In the previous post I talked about the Tech II clones and how the seller got busted. It is innacurate and misleading to consider any of the cheap code pullers as a diagnostic tool. There is so much more to doing diagnostics that even the Snap-On Solus can't do at over forty times the expense. (plus the updates for it that are over a grand each year)
Have you ever been to their diagnostic repair website? It isn't real hard to find and to join. Before any more praise is heaped on them, that really should be examined closely.
An oxygen sensor in an older car is a $168 part, according to CarMD data. Replacing it is a good idea. Ignoring it can lead to a more costly catalytic converter repair, which can cost more than $1,000.
O2 sensors and air/fuel sensors are all over the place when it comes to pricing. Some good ones are as little as $50 (there is trash that is even cheaper) and some are over $250. Catalysts as well can be a few hundred, to over $6000. The point is, why talk price at all without specifics that prove a genuine need, and then attempt to source the items? The way that is written I get the impression that the author wants to tell consumers to just replace their O2 sensor(s) and that will magically protect the catalysts. The first problem is, there are a lot of products on the store shelves that don't perform correctly and could in fact cause the owner to not only have a failure of a catalyst but it could cost them their PCM if the sensor causes the heater control circuit to fail in the PCM. If someone is truly worried about catalyst lifespan, they must immeadiately resolve any misfiring that may occur because nothing kills a catalyst as fast as a misfire does. Plus they should be changing the oil with one that meets the manufacturers specs and using the extended drain formats. Even that would be far more beneficial than just replacing the O2 sensors on the hunch that they may be lazy.
But lets say you really want to know if they are lazy or not. Simply connect a scan tool and pull up the mode five, or in a CAN car the mode six data and evaluate the O2 sensor test results. Ooops, CarMD can't do that can they? You need a real scan tool to access all of the system modes. Well you could grab a digital oscilloscope and measure the O2 sensor waveforms yourself, but testing like that is a single snapshot instead of the whole picture.
The person was found guilty of trafficking in counterfeit goods. Really no different than someone selling knockoff Rolex watches or knockoff Coach handbags.
My MINI lights up the dashboard like it's Christmas in April. I just take the scan tool and shut them off periodically--they are meaningless--I'm tired of chasing electronic ghosts that lead nowhere.
You've seen a Range Rover or Jag before, right? :shades:
Maybe I am lucky with MBs like Lemko is lucky with GMs, but I've had a total of 2 idiot light episodes in my history of MB ownership. Both easily solved (one a relay, one a brake light switch).
It was only designed during that administration :shades: That one doesn't really have idiot lights. It has a few warning lights (brake, generator, high beams, low fuel) - when they light up, there's a problem. I am driving it today, btw, as the new car has an annoying rattle, and as it has a warranty, I am making it useful. I suspect the service department will grow to hate me :shades:
I had a Christmas tree light up on my 1989 W126 300SE, which was a failed relay. I changed it myself. A few years ago, a similar Christmas tree on my 2002 E55 - took it to my preferred indy shop, was fixed in under an hour for about $100, IIRC.
My MINI lights up the dashboard like it's Christmas in April. I just take the scan tool and shut them off periodically--they are meaningless--I'm tired of chasing electronic ghosts that lead nowhere.
My wife's E36 3er had a phantom CEL, and her E39 5er also liked to light up the CEL and the ABS telltale. Contrast that with my 3er, which only illuminated its CEL once(when an idiot employee of the Tire Kingdom in Hilton Head removed the oil filler cap during a tire R&R) and my sons X3, which has never thrown a CEL. My Jeep has a phantom CELl I've never bothered to chase, while my Mazda threw a fuel trim and EGR flow CEL.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
2. Drive the car at highway speeds for the two weeks prior to the smog test. This gets the catalytic converter hot enough to burn out any oil and gas residues.
Has the OBDII monitor for the catalyst run anytime in the last few days? If so then it got hot enough to prove that its doing its job, and an extra set of needless road trips are avoided. Now some might not equate how the OBDII monitor works as compared to the ASM loaded test and it takes hours upon hours of study to really have the theory down but we can do a cliff notes version. OBDII cannot actually test the systems ability to control NOx directly. The engineers have to use modeling to estimate how hot the catalyst is, and from there they measure the catalysts ability to store O2. There is a direct relationship between that capability and the catalysts ability to reduce NOx. Controlling HC and CO is easy, as a lean mixture adds O2 to the exhaust to assist that reaction. Controlling NOx requires an absence of O2, so if the catalyst can absorb it, then the exhaust gas becomes depleted of O2 and then the catalyst can then the NOx apart (just like it was a rich exhaust). You have to picture this occurring at the molecular level today as reduction and oxidation occur through the entire convertor instead of in different beds as it used to.
The catalytic converter, mandated by federal law in 1974 for all U.S. cars and trucks, converts harmful pollutants into less harmful emissions before they leave the exhaust system. The worst thing for the proper operation of emissions systems is a series of short trips: The catalytic converter never gets hot enough to do its job, Mazor says.
If that was the case then we would have to use heated catalysts. Secondary air systems are used to assist in lighting off the catalysts during cold starts on many cars today. Upstream catalysts light off in under sixty seconds of driving time. Once the upstream cat is lit, the downstream catalyst follows rapidly behind.
We could talk about the catalyst lighting strategy on the gasoline direct injected engines too. With those the PCM commands the throttle open wider than normal and retards the ignition timing which allows the fuel to still be burning when the exhaust valve is open. Some manufacturers even give an extra fuel pulse at that time, and when that is combined with secondary air that really puts some heat into the exhaust.
An oddity that does occur is false fails for NOx during an ASM test when a catalyst meets the O.E's specifications. That often comes from the machine software that just happens to run the vehicle at just the right engine load that it is between operational conditions. The ASM test is a compromise and in that respect it is flawed and is both capable of passing cars that should fail, and failing cars that should have passed. OBDII solves that problem.
There is one other thing about the opening picture and the theme of the article. With the air depicted, the last thing anyone should want is a car that should fail to get an unwarranted pass. JMHO
The recent thread where I had my fun at Lances expense needs some closure. First, when encountering a catalyst code there are a few things that the technician must confirm. They are in no particular order that there are simply no TSB's or software updates. If the engineers got the testing wrong and the catalyst is failing falsely, or prematurely as Rags said that is where you will have your only chance to do something about it. If the engineers have not released an update to fix it, you don't have a chance to prove or disprove the catalysts ability to do its job, because as was said more times than I want to try and count, you'll still have to trust the PCM.
The next thing for the technician to check and rule out is exhaust leaks, and the performance of the O2 sensors. Exhaust leaks are pretty straight forward, they rarely play "Hide and Go Seek". Keep in mind, an O2 sensor that is marginal may pass the PCM's test of it, and then turn around and not be able to accurately report the exhaust content and trick the PCM into a false result. At the same time keep in mind for that to result in a false catalyst failure, it would have to occur two times in a row. That fact alone reduces the chances of that occurring, but does not eliminate the possibility.
The technician must verify good fuel control, and fuel trim. Exhaust leaks obviously have a potential impact on fuel trim, but so do certain input signals that the PCM relies on to recognize when its inside or outside of the designed testing window. Different manufacturers use different routines to establish their testing thresholds, GM typically tests at idle and they don't even have to of completed their O2 sensor monitors. If by chance one of the O2 monitors fail after the catalyst monitor has run, the decision could be made by the PCM to suspend the result depending on the results of the next test. Ford on the other hand runs the O2 sensor monitors, and then completes the catalyst testing under varying light load conditions. If the O2 sensor monitors do not complete, it should be expected that the Ford system will not even attempt to run the catalyst monitor. BTW, do leave room for exceptions as neither of these are hard facts, just tendencies. Always refer to service information for specific details on any vehicle you need to diagnose.
One of the biggest issues with P0420, and P0430 codes has to do with investigating why the catalyst failed in the first place. We can argue this one till the end of time but it's my opinion that far more catalysts are killed by external causes than simply die of old age. Sure both types of catalyst death occur and I have no statistics to prove my assertion that converters are more commonly killed than get to live to old age. But in a limited study of two vehicles to support my take on the matter I do have data that I collected from have two rather common vehicles, a 1999 F150 with 287K miles, and a 2002 Ford Explorer with 143K that both have all of their original catalysts on them and all of them are still going strong.
[1999 Ford F-150, Emissions Scan Data] [Fig. 1]
These two captures show the mode 6 data for the catalyst tests. Since this was a featured article, the public is supposed to be able to see them on the iATN site.
[2002 Ford Explorer XLT, Emissions Scan Data] [Fig. 2]
Now when you look at those captures for the catalyst you see the pids called rear to front switch ratio. Things like that, and descriptions from many manufacturers about how they compare the O2 sensors outputs during the onboard testing of the catalysts is what I believe leads to the misconception that technicians in the field should be able to evaluate a catalyst by watching the sensors. Let's see if we can explain why it just won't work for us, and it's not about what we can see which are the O2 sensor signals, its all about what we can't see and that is exactly how efficient the catalyst should be right at the time the technician is looking at the data.
There are a lot of things to consider about a catalyst and how efficient it should be. Of course the age of the assembly is important, and when it comes to replacement catalysts, construction and its size (the volume of and the percentage of the elements inside it) are critical. But for now, lets concentrate on just the O.E. version and what we can ascertain. When the engineers set up to test a catalysts efficiency and of course to decide when it is no longer capable of doing the job that it has been assigned they took on the task of trying to predict what the converter would do under a specific range of conditions. To do that they rely on a process called modeling. The short and not perfectly accurate explanation of modeling would be where they first had to predict if the vehicle was driven under specific conditions that the catalyst would be a specific temperature. Then with a given airflow (engine load), fuel trim, engine rpm, and the heck if I know what all else, the locus length of the upstream sensor would be XX times longer than that of the downstream one.
Locus length is pretty well defined by another member of the iATN as the length of a piece of a string that if you took a specific period of time and graphed out the O2 sensor, you could lay that string on top of the graph and measure its length. You would then repeat that for the down stream sensor and measure that string for the same period of time, and that ratio between them is the answer to how well the catalyst worked at that moment. As a technician, you could see sensor output that could easily be interpreted as the converter operating, but you could also see just the opposite result at any point in time. You have no way to know just how efficient the converter should be right now, if it is even lit off at all. Even worse, you could accidentally be looking at the sensors while the PCM is actually running the test, and its intentionally forcing the rear O2 sensor to move and it would easily look like a bad catalyst to you, when the PCM happens to be ready to pass it.
If you had a way to know exactly what the sensors outputs should be at a given catalyst temperature, and engine load, and every other variable that the engineers decided was pertinent, then and only then could you try and make sense from the sensor outputs. But even that would be only for that one specific moment in time, and not necessarily through the catalysts entire expected range of operation.
By modeling the engineers work to predict what the catalyst will do under a wide range of conditions and one that (just) passes under one specific set of circumstances may fail under others.
So what does all of this mean? When you retrieve a P0420/P0430, inspect for the things that you have the ability to check, and in their absence there is nothing else you can do but trust the PCM, and make sure to the best of your ability that there are no conditions with the vehicle that are likely to kill the new one.
I was on my way to a vacation in Hilton Head and hit a pothole, ruining the RF tire. I was driving the Club Sport, which does use a bit of oil(1 qt. every 3000 miles or so), so I checked the oil at every fuel stop AND when I got to Hilton Head. I NEVER added any oil. Fast forward three days-I'm at the Hilton Head Tire Kingdom having my tire replaced. On the way back to the condo I smell burning oil and the CEL illuminates. I pull over, pop the hood, and find that my oil filler cap is missing. I call Tire Kingdom and they treat me like an idiot: "Sir, you need to go back to the shop that changed your oil." Funny thing, I drove the car from the Ohio Valley to SC and never smelled any oil or noticed the CEL... Luckily, I found the cap laying on top of the motor mount. After an hour of scrubbing and a roll of paper towels the engine bay was presentable again. My guess is that some idiot at Tire Kingdom thought the car was in for an oil change and got ready to pull the drain plug when someone yelled "No, Goober! That 'uns jest here to git the tar changed." So, Goober closes the hood without replacing the cap.
What really got me about the entire debacle was the fact that they shouldn't have been anywhere near the underhood area. I also didn't appreciate being treated like I didn't know what I was talking about. I wasn't seeking any restitution- a simple "We're sorry." would have been sufficient.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
I call Tire Kingdom and they treat me like an idiot..
My guess is that some idiot at Tire Kingdom thought the car was in for an oil change and got ready to pull the drain plug when someone yelled "No, Goober! That 'uns jest here to git the tar changed." So, Goober closes the hood without replacing the cap.
That's a good guess, but you don't know if that is what happened for certain.
What really got me about the entire debacle was the fact that they shouldn't have been anywhere near the underhood area.
There are very good reasons to lift the hood on every car that comes into the shop. That action prevents claims like "It must have been low on oil and it was just in the shop and the mechanic didn't check it so it's his fault that the engine blew up". Consumers often love to twist their claims from its wrong to check the oil, to its wrong to not check the oil for whatever flavor of the moment works to their advantage.
I also didn't appreciate being treated like I didn't know what I was talking about
Nobody likes being treated that way, and you didn't like it in the past when I saw that in your posts about mechanics. There are some gaps in your story. You might have guessed correctly, but there is plenty of room for you to have guessed incorrectly.
Prove that you really do know what you are talking about. Lets see if you can use the theory of how and why the Mil illuminated to potentially discredit your own guess.
There are very good reasons to lift the hood on every car that comes into the shop. That action prevents claims like "It must have been low on oil and it was just in the shop and the mechanic didn't check it so it's his fault that the engine blew up". Consumers often love to twist their claims from its wrong to check the oil, to its wrong to not check the oil for whatever flavor of the moment works to their advantage.
Why am I at all not surprised that you would come up with a reason that justified Tire Kingdom's obvious mistake? I was virtually certain that you would have an explanation as to why they removed-and forgot to replace-an oil filler cap when the car was only in the shop to have the RF tire changed.
Nobody likes being treated that way, and you didn't like it in the past when I saw that in your posts about mechanics. And who did I treat badly? I may have believed that some techs or shops were incompetent, but I never told them that.
There are some gaps in your story. You might have guessed correctly, but there is plenty of room for you to have guessed incorrectly.
Gaps? That's hysterical. I took the car to Tire Kingdom to have a new tire installed. I sit in the waiting room and when the car is returned @45 minutes later the oil filler cap has been removed and the car throws a CEL shortly thereafter. Oh wait, I must have made up part of the story. Whatever part I left out-or failed to fabricate-contains the one bit of critical information that explains why Tire Kingdom's conduct was 100% correct under the circumstances.
Prove that you really do know what you are talking about. Lets see if you can use the theory of how and why the Mil illuminated to potentially discredit your own guess.
The car through a CEL because the missing oil filler cap created a huge vacuum leak. And the light extinguished itself when the cap was replaced. I'm sure you have a ready explanation that justifies the shop forgetting to replace the cap when they weren't even working on the engine...
You claim that you to want to raise the standards of your profession, yet you rush to excuse or shift the blame when other mechanics screw up. Is there anything that a shop could do wrong that you wouldn't attempt to explain away? Or blame on the customer?
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
Why am I at all not surprised that you would come up with a reason that justified Tire Kingdom's obvious mistake? I was virtually certain that you would have an explanation as to why they removed-and forgot to replace-an oil filler cap when the car was only in the shop to have the RF tire changed
I'm neither justifying it, nor defending them IF that's what really happened.
Gaps? That's hysterical. I took the car to Tire Kingdom to have a new tire installed. I sit in the waiting room
Yea Gaps, like why would you be checking the oil every 400 miles when you have a known history of useage of a quart every 3000?
Why would someone as capable as you not simply drop off your wheel and tire, and then pick it up and install it yourself? (making sure to use a torque wrench to re-install the wheel)
The car through a CEL because the missing oil filler cap created a huge vacuum leak. And the light extinguished itself when the cap was replaced. I'm sure you have a ready explanation that justifies the shop forgetting to replace the cap when they weren't even working on the engine...
Yawn... Anybody can guess that with minimal knowledge and experience. Show us what you really know. What code set. What was the enabling criteria. Heck by the time I write this all out and ask for the specifics I'd virtually hand you the answers. I don't want to do that, this is about what you know, not what I can coach you to.
I asked you to try and argue against your guess using service information. If you can't succeed in that exercise using accurate information then you would gain strength in your argument. However if you succeed in making the argument against your guess then you have to take a step back and reconsider. Are you afraid to try and do that or what?
cardoc, I have never visited this forum before, just checking it out, but man, are you serious?
You seem to be taking a very logical common sense situation, presented in good faith by a poster, and twisting it so much that you eventually call the poster and liar and ask him follow your instructions to prove that he is incompetent.
You may think you are mounting a defense for mechanics, but what you are doing is proving how deceptive they can be. In fact, you are doing a great disservice to all honest forthright mechanics. Think about it.
Why would someone as capable as you not simply drop off your wheel and tire, and then pick it up and install it yourself? (making sure to use a torque wrench to re-install the wheel)
How? By taking it there in a taxi? Perhaps rolling it there by hand?
He wasn't at home, but on holiday at Hilton Head Island. I doubt he took a full compliment of shop tools with him. I wouldn't.
On the oil front, I was taught to check the oil level at EVERY fillup. Reliability of cars has improved so much over the years that I don't do that any more, but a lot of people still do. AFAIK, no one ever damaged their vehicle by checking the oil level too often....
You may think you are mounting a defense for mechanics, but what you are doing is proving how deceptive they can be. In fact, you are doing a great disservice to all honest forthright mechanics. Think about it.
So anyone can write whatever story they want to as long as they don't let the facts get in the way, and the mechanics are always the ones who are wrong.
C'mon now doc...there were no CEL's for the whole trip. If it wasn't on tight, there would have been. There really just aren't that many other logical explanations. If RB used a dash cam (something more and more bikers are using now to prove their innocence when being harassed by less than honorable cops, or other drivers trying to use their car as a weapon to hurt or kill you) then he could pull up the 'tape' and see if his theory was right or not.
It is a shame that throughout your 30+? years as a tech that past experiences, it seems.. has created the size chip that you do seem to have on your shoulders all the time.
When I see you write at times... "JMHO", I chuckle out loud, cuz there is nothing humble about you. You can take on anybody, anytime, anywhere but there are times you don't back down even when the most obvious thing to do would be swallow and do just that. Perish the thought...but concede maybe, that the rest of the motoring world are not wrong 100% of the time ya know..
I may be teasing you here, but I do admire the knowledge that you have worked hard over the years to acquire and further.. keep up to date progressively. I have seen enough in this forum and have read your blog, and have witnessed first hand in a couple examples how your brain works and how you trouble-shoot and I sorta know why you are as defensive as you are. I was going to say "most times", but can't really say that. You are defensive basically all the time. That is why I said above that for a profession that you take obvious and well-deserved pride in, you have been beatin' up as bad as it seems you have been over the years. I think what is happening is that pain makes a person less patient and tolerant. I speak from personal experience on that front. And factor in a killing back and screwed knees and dealing with one too many mindless customers (hopefully they are farther and fewer between due to your screening, but they're still gonna surface at times) one day and whammo, you are in full-on defense mode. The off switch no longer works. But you are a true, if not perfectionist, auto technician.
That said, this is a great forum, and if you weren't here with your input at times, it'd be dead pretty fast I think.
I was going to post another response, but the other participants beat me to it. At this point I'm taking a hiatus from this forum; life is too short to waste my time arguing with a "professional" who assumes that anyone who has the temerity to disagree with them is either a liar and or a dolt.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
I guess I see it exactly the same as you, Gimmestdtranny.
Cardoc, there's no question that, from a technical expertise, you're the guy I'd want working on my car. You are methodical in your approach, and thorough in your analysis.
Having said that, and I sincerely say this with the utmost respect for you, you're not the only guy out there that can fix cars. Lighten up a bit, or one day you're going to wake up dead from all the self-imposed stress.
One last comment... Baiting a fellow poster is anything but professional. Just as you would have me tell a tech he was mistaken in the way he was doing something (when there's no question he's in the wrong) so that he could learn from the experience, don't you think turn-around is fair play?
No it was none of that. It was simply the fact that RB again had to use language that is insulting and its time he felt what its like to be a tech when that happens.
He thought that he knew enough about why the check engine light came on to view himself as competent, but when really challenged didn't even know where to start. In a shop setting, that gap in knowledge would have him be no better than the tech he claims made a mistake and called an idiot. Assuming he is guessing correctly, the tech was still no more of an idiot than RB would be for not being able to explain the exact perameters that went into play for the PCM to command the MIL. Yea, I have to be a B#$D to put that much pressure on him, but what do you think it is like in the shop when something like this goes down? That's what its like being a tech and we would get told, if we can't stand the heat get out of the kitchen .
When I teach ODBII fuel trim diagnostics and repairs, and what it takes to get a car ready for emissions testing, with some failures I instruct the techs to not clear the codes. We make the correct repair and then I show them how to get the car ready to pass the emissions test by simply getting the car to pass the test that had been failing and then the car turns off the MIL on its own. That saves time and money for the shop and the consumer. But other failures make more sense to clear the codes, reset the memory and start from fresh because they will take too long to clear and running all of the monitors make more sense time wise. A fuel control issue is one of those examples. Trying to wait for the system to self clear when you have had a problem such as a lean engine is a condition is better addressed by clearing the codes because of what the system has to do to make sure that the O2's are operating correctly, and then begin the relearning process. In short, the light doesn't just go right out and many functions are blocked by the presence of the lean code.
In this trade, a tech can be right more than 99% of the time but the one time he/she falters for any reason they are an idiot in RB's eyes. I want him to know how that feels.
Beautiful day, put the top down and drove it (with expired tabs) around long enough to get it good and warmed up, drove to the emission testing place praying my CEL wouldn't come on and it didn't!
I do the same thing with my old Mustang. Wait for a warm day, take it out on the highway and put in 'Drive' to get some extra revs for a few miles, then go to the test site. Since it's a 1991, it has to be tested on the rollers.
2024 Ford F-150 STX, 2023 Ford Explorer ST, 91 Mustang GT vert
Emissions testing? We (Kentucky) got rid of that rip off over a decade ago. Does it really do any good? Other than making the owners of the testing centers rich?:-(
BTW, What do you call the person who graduated last in their class at medical school?
But back to your dictum, if it was intended to represent reality, they should be thinking cattle which makes the point that your bound to be wrong more often by guessing than you are by testing.
I wonder if my fintail could overload and kill their testing equipment. What's a catalytic converter?
LOL. No it won't overload the machine, but the particulate filter will need to be changed. But there is a reason that they push thse cars through the auctions instead of drive them and its not the sound from the engine that has them do that.
For the life of me I have to wonder WHY a person changing a tire wold even open the hood of a car? I've NEVER EVER seen a shop do such a thing.
The chain stores would write a tech up for not checking the fluids, belts, hoses, etc. That's how hungry they are for those $$$$. Don't sell enough? Find another place to work.
And, WHY would a tire guy remove an oil car? For what possible reason?
Now you've gone and done it, you asked the question that requires more than just speculation. In short, they wouldn't. But it seems all someone needs to do is make a story that arrives at the conclusion that they want it to and the shop/tech is at fault. No proof required.
In Maryland, they do emissions testing by county, and they do it where I live. However, where my Mom and stepdad live, in Southern Maryland, they don't. Apparently the county did a cost/benefit analysis, and calculated that building the facility, damage to the environment (water runoff and heat-sink from buildings and parking lot, versus trees and such), all the time those cars spend idling waiting in line, driving to and from the emissions test, etc, would actually do more harm than good for the environment!
Now, population does have something to do with it, to be sure. My county has about 881,000 people in in. Where my Mom lives, it's only around 109,000.
Oh, and the testing centers here are owned and operated by either the state or county, not sure which. So, while it may not make a station owner rich, it probably helps out a politician or two!
Comments
The OBDII system is emissions testing built right into the car. That means your car is being tested every time you use it, and if the light comes on, that means that it failed part of the test. Some areas have a monitored system, others rely on the owners to have their cars serviced.
Also in Maryland, it used to be that if your vehicle failed the emissions test, you could get a waiver if you could show that you spent $450(?) on emissions related work to try and correct the problem. My '87 BMW was notorious for just barely failing the NOx part of the test. So I would always wait until I failed the test to have work done that might affect emissions
That was pre-OBDII and may have been a broken car, and may not have. the dyno-tests were capable of a lot of false failures, but like any of the programs they were a compromise that had more successes than failures. High Nox can be caused by poor (insufficient) EGR flow as well as a weak catalyst, or a system that is too lean to allow the catalyst to function correctly. It's also possible that it was a false fail that had the vehicle tested at just the right speed where a particular car simply didn't work efficiently. That's why OBDII is better BTW.
What year did OBDII begin?
1996- for BMWs at least.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
It became mandatory in 1996 in all US automobiles.
Today full diagnostic capabilities on some cars still requires the use of connectors other than the 16 pin ALDL. Keep in mind OBDII is an emissions system, and wasn't actually built as a diagnostics platform.
I bought my Tech II in 2001, it was the first O.E. tool that I stepped up and purchased. The difference in its capabilities as compared to the Snap-On MT2500 (Red Brick), and my Vetronix Master Tech at that time was eye opening. My Snap-On had been purchased some seven years before that and had been upgraded once, and with all of the updates probably represented some $15,000. (That has since doubled today with the change to the Solus, and the continuing upgrades). The Master tech was a $13,000 purchase in 1999, and with updates and getting the Toyota (08), Honda(04), and Nissan (08) factory upgrades for it represents some $20,000. Upon seeing what the O.E. tools could do as compared to what the aftermarket versions could we added the Ford IDS to our list, and Chryslers DRBIII, and StarScan for a grand total today that is over $100,000 for all of them and that total invested continues to climb each year.
My Tech II has grown to represent over $20,000 invested all by itself, but you cannot do the job correctly without it on the GM vehicles. Then one day the cloned tools started showing up on E-bay. People could purchase a current year cloned Tech II ($1500) for just about what the yearly update was costing me ($1395). At first we didn't know what they were, and thought they could be stolen, or subject of a business closing, until we realized that they had current software and that didn't make any sense to sell it that cheap. Then the word came out that these were clones, counterfeits, and we found that out by some of the tools breaking and the purchaser sending it in to have it repaired, only to have Bosch (Vetronix) confiscate the tool.
The article linked is only a drop in the bucket as to how many of these that are out there, but its a start. Try and imagine how it felt to see someone spend $1500, and get to pull even tool wise where I had over $20,000 invested. The one thing that they are failing to do here is recover the counterfeit tools, and then let the purchasers go back after the seller. Part of the solution for the tool counter-fitting is the switch to the laptop based tools that we only get a license to use the software for a limited period of time. At least with the Tech II purchase, as well as the NGS, DRBIII, StarScan, they may be limited by model and year, but they continue to work even if there are no more updates. The laptop based tools turn off when their license expires.
Gee, today the most common cause for a check engine light is now an O2 sensor? Didn't it used to be the gas cap? The reality is that there isn't one single likely cause, and every even needs to be diagnosed and repaired correctly as an individual occurrance. That's the fatal flaw with CarMD's approach. It sells their $100 toy tool, and like a chinese auction some people do get lucky with it, but most do not. Some keep changing parts until they have spent a small fortune and still haven't repaired the car only to find out we would have been far less expensive of a choice.
which sells an automotive diagnostic tool and provides repair information. Sometimes, even before an oxygen sensor fails, it becomes "lazy," not properly regulating the gas/air mixture, and that will cause a smog check failure, Mazor says.
In the previous post I talked about the Tech II clones and how the seller got busted. It is innacurate and misleading to consider any of the cheap code pullers as a diagnostic tool. There is so much more to doing diagnostics that even the Snap-On Solus can't do at over forty times the expense. (plus the updates for it that are over a grand each year)
Have you ever been to their diagnostic repair website? It isn't real hard to find and to join. Before any more praise is heaped on them, that really should be examined closely.
An oxygen sensor in an older car is a $168 part, according to CarMD data. Replacing it is a good idea. Ignoring it can lead to a more costly catalytic converter repair, which can cost more than $1,000.
O2 sensors and air/fuel sensors are all over the place when it comes to pricing. Some good ones are as little as $50 (there is trash that is even cheaper) and some are over $250. Catalysts as well can be a few hundred, to over $6000. The point is, why talk price at all without specifics that prove a genuine need, and then attempt to source the items? The way that is written I get the impression that the author wants to tell consumers to just replace their O2 sensor(s) and that will magically protect the catalysts. The first problem is, there are a lot of products on the store shelves that don't perform correctly and could in fact cause the owner to not only have a failure of a catalyst but it could cost them their PCM if the sensor causes the heater control circuit to fail in the PCM. If someone is truly worried about catalyst lifespan, they must immeadiately resolve any misfiring that may occur because nothing kills a catalyst as fast as a misfire does. Plus they should be changing the oil with one that meets the manufacturers specs and using the extended drain formats. Even that would be far more beneficial than just replacing the O2 sensors on the hunch that they may be lazy.
But lets say you really want to know if they are lazy or not. Simply connect a scan tool and pull up the mode five, or in a CAN car the mode six data and evaluate the O2 sensor test results. Ooops, CarMD can't do that can they? You need a real scan tool to access all of the system modes. Well you could grab a digital oscilloscope and measure the O2 sensor waveforms yourself, but testing like that is a single snapshot instead of the whole picture.
The person was found guilty of trafficking in counterfeit goods. Really no different than someone selling knockoff Rolex watches or knockoff Coach handbags.
Tell me about it as I'm heading down to pull my 328i 'vert out of the garage in yet another attempt to get it to psss emissions!
Ths teutonic, prissy little car is going to be the end of me!
If it's not one warning light, it's another!
Maybe I am lucky with MBs like Lemko is lucky with GMs, but I've had a total of 2 idiot light episodes in my history of MB ownership. Both easily solved (one a relay, one a brake light switch).
I had a Christmas tree light up on my 1989 W126 300SE, which was a failed relay. I changed it myself. A few years ago, a similar Christmas tree on my 2002 E55 - took it to my preferred indy shop, was fixed in under an hour for about $100, IIRC.
My wife's E36 3er had a phantom CEL, and her E39 5er also liked to light up the CEL and the ABS telltale. Contrast that with my 3er, which only illuminated its CEL once(when an idiot employee of the Tire Kingdom in Hilton Head removed the oil filler cap during a tire R&R) and my sons X3, which has never thrown a CEL.
My Jeep has a phantom CELl I've never bothered to chase, while my Mazda threw a fuel trim and EGR flow CEL.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
Care to explain the specifics on this?
Has the OBDII monitor for the catalyst run anytime in the last few days? If so then it got hot enough to prove that its doing its job, and an extra set of needless road trips are avoided. Now some might not equate how the OBDII monitor works as compared to the ASM loaded test and it takes hours upon hours of study to really have the theory down but we can do a cliff notes version. OBDII cannot actually test the systems ability to control NOx directly. The engineers have to use modeling to estimate how hot the catalyst is, and from there they measure the catalysts ability to store O2. There is a direct relationship between that capability and the catalysts ability to reduce NOx. Controlling HC and CO is easy, as a lean mixture adds O2 to the exhaust to assist that reaction. Controlling NOx requires an absence of O2, so if the catalyst can absorb it, then the exhaust gas becomes depleted of O2 and then the catalyst can then the NOx apart (just like it was a rich exhaust). You have to picture this occurring at the molecular level today as reduction and oxidation occur through the entire convertor instead of in different beds as it used to.
The catalytic converter, mandated by federal law in 1974 for all U.S. cars and trucks, converts harmful pollutants into less harmful emissions before they leave the exhaust system. The worst thing for the proper operation of emissions systems is a series of short trips: The catalytic converter never gets hot enough to do its job, Mazor says.
If that was the case then we would have to use heated catalysts. Secondary air systems are used to assist in lighting off the catalysts during cold starts on many cars today. Upstream catalysts light off in under sixty seconds of driving time. Once the upstream cat is lit, the downstream catalyst follows rapidly behind.
We could talk about the catalyst lighting strategy on the gasoline direct injected engines too. With those the PCM commands the throttle open wider than normal and retards the ignition timing which allows the fuel to still be burning when the exhaust valve is open. Some manufacturers even give an extra fuel pulse at that time, and when that is combined with secondary air that really puts some heat into the exhaust.
An oddity that does occur is false fails for NOx during an ASM test when a catalyst meets the O.E's specifications. That often comes from the machine software that just happens to run the vehicle at just the right engine load that it is between operational conditions. The ASM test is a compromise and in that respect it is flawed and is both capable of passing cars that should fail, and failing cars that should have passed. OBDII solves that problem.
There is one other thing about the opening picture and the theme of the article. With the air depicted, the last thing anyone should want is a car that should fail to get an unwarranted pass. JMHO
No You Can't Use The O2 Sensors To Judge A Cat.
The recent thread where I had my fun at Lances expense needs
some closure. First, when encountering a catalyst code there
are a few things that the technician must confirm. They are
in no particular order that there are simply no TSB's or
software updates. If the engineers got the testing wrong and
the catalyst is failing falsely, or prematurely as Rags said
that is where you will have your only chance to do something
about it. If the engineers have not released an update to
fix it, you don't have a chance to prove or disprove the
catalysts ability to do its job, because as was said more
times than I want to try and count, you'll still have to
trust the PCM.
The next thing for the technician to check and rule out is
exhaust leaks, and the performance of the O2 sensors.
Exhaust leaks are pretty straight forward, they rarely play
"Hide and Go Seek". Keep in mind, an O2 sensor that is
marginal may pass the PCM's test of it, and then turn around
and not be able to accurately report the exhaust content and
trick the PCM into a false result. At the same time keep in
mind for that to result in a false catalyst failure, it
would have to occur two times in a row. That fact alone
reduces the chances of that occurring, but does not
eliminate the possibility.
The technician must verify good fuel control, and fuel trim.
Exhaust leaks obviously have a potential impact on fuel
trim, but so do certain input signals that the PCM relies on
to recognize when its inside or outside of the designed
testing window. Different manufacturers use different
routines to establish their testing thresholds, GM typically
tests at idle and they don't even have to of completed their
O2 sensor monitors. If by chance one of the O2 monitors fail
after the catalyst monitor has run, the decision could be
made by the PCM to suspend the result depending on the
results of the next test. Ford on the other hand runs the O2
sensor monitors, and then completes the catalyst testing
under varying light load conditions. If the O2 sensor
monitors do not complete, it should be expected that the
Ford system will not even attempt to run the catalyst
monitor. BTW, do leave room for exceptions as neither of
these are hard facts, just tendencies. Always refer to
service information for specific details on any vehicle you
need to diagnose.
One of the biggest issues with P0420, and P0430 codes has to
do with investigating why the catalyst failed in the first
place. We can argue this one till the end of time but it's
my opinion that far more catalysts are killed by external
causes than simply die of old age. Sure both types of
catalyst death occur and I have no statistics to prove my
assertion that converters are more commonly killed than get
to live to old age. But in a limited study of two vehicles
to support my take on the matter I do have data that I
collected from have two rather common vehicles, a 1999 F150
with 287K miles, and a 2002 Ford Explorer with 143K that
both have all of their original catalysts on them and all of
them are still going strong.
[1999 Ford F-150, Emissions Scan Data] [Fig. 1]
These two captures show the mode 6 data for the catalyst tests. Since this was a featured article, the public is supposed to be able to see them on the iATN site.
[2002 Ford Explorer XLT, Emissions Scan Data] [Fig. 2]
Now when you look at those captures for the catalyst you see
the pids called rear to front switch ratio. Things like
that, and descriptions from many manufacturers about how
they compare the O2 sensors outputs during the onboard
testing of the catalysts is what I believe leads to the
misconception that technicians in the field should be able
to evaluate a catalyst by watching the sensors. Let's see if
we can explain why it just won't work for us, and it's not
about what we can see which are the O2 sensor signals, its
all about what we can't see and that is exactly how
efficient the catalyst should be right at the time the
technician is looking at the data.
There are a lot of things to consider about a catalyst and
how efficient it should be. Of course the age of the
assembly is important, and when it comes to replacement
catalysts, construction and its size (the volume of and the
percentage of the elements inside it) are critical. But for
now, lets concentrate on just the O.E. version and what we
can ascertain. When the engineers set up to test a catalysts
efficiency and of course to decide when it is no longer
capable of doing the job that it has been assigned they took
on the task of trying to predict what the converter would do
under a specific range of conditions. To do that they rely
on a process called modeling. The short and not perfectly
accurate explanation of modeling would be where they first
had to predict if the vehicle was driven under specific
conditions that the catalyst would be a specific
temperature. Then with a given airflow (engine load), fuel
trim, engine rpm, and the heck if I know what all else, the
locus length of the upstream sensor would be XX times longer
than that of the downstream one.
Locus length is pretty well defined by another member of the
iATN as the length of a piece of a string that if you took a
specific period of time and graphed out the O2 sensor, you
could lay that string on top of the graph and measure its
length. You would then repeat that for the down stream
sensor and measure that string for the same period of time,
and that ratio between them is the answer to how well the
catalyst worked at that moment. As a technician, you could
see sensor output that could easily be interpreted as the
converter operating, but you could also see just the
opposite result at any point in time. You have no way to
know just how efficient the converter should be right now,
if it is even lit off at all. Even worse, you could
accidentally be looking at the sensors while the PCM is
actually running the test, and its intentionally forcing the
rear O2 sensor to move and it would easily look like a bad
catalyst to you, when the PCM happens to be ready to pass
it.
If you had a way to know exactly what the sensors outputs
should be at a given catalyst temperature, and engine load,
and every other variable that the engineers decided was
pertinent, then and only then could you try and make sense
from the sensor outputs. But even that would be only for
that one specific moment in time, and not necessarily
through the catalysts entire expected range of operation.
By modeling the engineers work to predict what the catalyst
will do under a wide range of conditions and one that (just)
passes under one specific set of circumstances may fail
under others.
So what does all of this mean? When you retrieve a
P0420/P0430, inspect for the things that you have the
ability to check, and in their absence there is nothing else
you can do but trust the PCM, and make sure to the best of
your ability that there are no conditions with the vehicle
that are likely to kill the new one.
You asked for it...
I was on my way to a vacation in Hilton Head and hit a pothole, ruining the RF tire. I was driving the Club Sport, which does use a bit of oil(1 qt. every 3000 miles or so), so I checked the oil at every fuel stop AND when I got to Hilton Head. I NEVER added any oil. Fast forward three days-I'm at the Hilton Head Tire Kingdom having my tire replaced. On the way back to the condo I smell burning oil and the CEL illuminates. I pull over, pop the hood, and find that my oil filler cap is missing. I call Tire Kingdom and they treat me like an idiot: "Sir, you need to go back to the shop that changed your oil." Funny thing, I drove the car from the Ohio Valley to SC and never smelled any oil or noticed the CEL... Luckily, I found the cap laying on top of the motor mount. After an hour of scrubbing and a roll of paper towels the engine bay was presentable again. My guess is that some idiot at Tire Kingdom thought the car was in for an oil change and got ready to pull the drain plug when someone yelled "No, Goober! That 'uns jest here to git the tar changed." So, Goober closes the hood without replacing the cap.
What really got me about the entire debacle was the fact that they shouldn't have been anywhere near the underhood area. I also didn't appreciate being treated like I didn't know what I was talking about. I wasn't seeking any restitution- a simple "We're sorry." would have been sufficient.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
You're correct, I did.
I call Tire Kingdom and they treat me like an idiot..
My guess is that some idiot at Tire Kingdom thought the car was in for an oil change and got ready to pull the drain plug when someone yelled "No, Goober! That 'uns jest here to git the tar changed." So, Goober closes the hood without replacing the cap.
That's a good guess, but you don't know if that is what happened for certain.
What really got me about the entire debacle was the fact that they shouldn't have been anywhere near the underhood area.
There are very good reasons to lift the hood on every car that comes into the shop. That action prevents claims like "It must have been low on oil and it was just in the shop and the mechanic didn't check it so it's his fault that the engine blew up". Consumers often love to twist their claims from its wrong to check the oil, to its wrong to not check the oil for whatever flavor of the moment works to their advantage.
I also didn't appreciate being treated like I didn't know what I was talking about
Nobody likes being treated that way, and you didn't like it in the past when I saw that in your posts about mechanics. There are some gaps in your story. You might have guessed correctly, but there is plenty of room for you to have guessed incorrectly.
Prove that you really do know what you are talking about. Lets see if you can use the theory of how and why the Mil illuminated to potentially discredit your own guess.
Why am I at all not surprised that you would come up with a reason that justified Tire Kingdom's obvious mistake? I was virtually certain that you would have an explanation as to why they removed-and forgot to replace-an oil filler cap when the car was only in the shop to have the RF tire changed.
Nobody likes being treated that way, and you didn't like it in the past when I saw that in your posts about mechanics.
And who did I treat badly? I may have believed that some techs or shops were incompetent, but I never told them that.
There are some gaps in your story. You might have guessed correctly, but there is plenty of room for you to have guessed incorrectly.
Gaps? That's hysterical. I took the car to Tire Kingdom to have a new tire installed. I sit in the waiting room and when the car is returned @45 minutes later the oil filler cap has been removed and the car throws a CEL shortly thereafter. Oh wait, I must have made up part of the story. Whatever part I left out-or failed to fabricate-contains the one bit of critical information that explains why Tire Kingdom's conduct was 100% correct under the circumstances.
Prove that you really do know what you are talking about. Lets see if you can use the theory of how and why the Mil illuminated to potentially discredit your own guess.
The car through a CEL because the missing oil filler cap created a huge vacuum leak. And the light extinguished itself when the cap was replaced. I'm sure you have a ready explanation that justifies the shop forgetting to replace the cap when they weren't even working on the engine...
You claim that you to want to raise the standards of your profession, yet you rush to excuse or shift the blame when other mechanics screw up. Is there anything that a shop could do wrong that you wouldn't attempt to explain away?
Or blame on the customer?
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
I'm neither justifying it, nor defending them IF that's what really happened.
Gaps? That's hysterical. I took the car to Tire Kingdom to have a new tire installed. I sit in the waiting room
Yea Gaps, like why would you be checking the oil every 400 miles when you have a known history of useage of a quart every 3000?
Why would someone as capable as you not simply drop off your wheel and tire, and then pick it up and install it yourself? (making sure to use a torque wrench to re-install the wheel)
The car through a CEL because the missing oil filler cap created a huge vacuum leak. And the light extinguished itself when the cap was replaced. I'm sure you have a ready explanation that justifies the shop forgetting to replace the cap when they weren't even working on the engine...
Yawn... Anybody can guess that with minimal knowledge and experience. Show us what you really know. What code set. What was the enabling criteria. Heck by the time I write this all out and ask for the specifics I'd virtually hand you the answers. I don't want to do that, this is about what you know, not what I can coach you to.
I asked you to try and argue against your guess using service information. If you can't succeed in that exercise using accurate information then you would gain strength in your argument. However if you succeed in making the argument against your guess then you have to take a step back and reconsider. Are you afraid to try and do that or what?
You seem to be taking a very logical common sense situation, presented in good faith by a poster, and twisting it so much that you eventually call the poster and liar and ask him follow your instructions to prove that he is incompetent.
You may think you are mounting a defense for mechanics, but what you are doing is proving how deceptive they can be. In fact, you are doing a great disservice to all honest forthright mechanics. Think about it.
2013 LX 570 2016 LS 460
How? By taking it there in a taxi? Perhaps rolling it there by hand?
He wasn't at home, but on holiday at Hilton Head Island. I doubt he took a full compliment of shop tools with him. I wouldn't.
On the oil front, I was taught to check the oil level at EVERY fillup. Reliability of cars has improved so much over the years that I don't do that any more, but a lot of people still do. AFAIK, no one ever damaged their vehicle by checking the oil level too often....
https://www.surveymonkey.com/s/EdmundsForums
Your input is greatly appreciated!
Great question. I normally expect cars to have a functional spare, but its true that not all do today.
He wasn't at home, but on holiday at Hilton Head Island. I doubt he took a full compliment of shop tools with him. I wouldn't.
Yea, but you haven't repeatedly presented a general disdain for repair shops either.
So anyone can write whatever story they want to as long as they don't let the facts get in the way, and the mechanics are always the ones who are wrong.
What other explaination could there be? Seems pretty cut and dry to this former tech.
It is a shame that throughout your 30+? years as a tech that past experiences, it seems.. has created the size chip that you do seem to have on your shoulders all the time.
When I see you write at times... "JMHO", I chuckle out loud, cuz there is nothing humble about you. You can take on anybody, anytime, anywhere but there are times you don't back down even when the most obvious thing to do would be swallow and do just that. Perish the thought...but concede maybe, that the rest of the motoring world are not wrong 100% of the time ya know..
I may be teasing you here, but I do admire the knowledge that you have worked hard over the years to acquire and further.. keep up to date progressively. I have seen enough in this forum and have read your blog, and have witnessed first hand in a couple examples how your brain works and how you trouble-shoot and I sorta know why you are as defensive as you are. I was going to say "most times", but can't really say that. You are defensive basically all the time. That is why I said above that for a profession that you take obvious and well-deserved pride in, you have been beatin' up as bad as it seems you have been over the years. I think what is happening is that pain makes a person less patient and tolerant. I speak from personal experience on that front. And factor in a killing back and screwed knees and dealing with one too many mindless customers (hopefully they are farther and fewer between due to your screening, but they're still gonna surface at times) one day and whammo, you are in full-on defense mode. The off switch no longer works. But you are a true, if not perfectionist, auto technician.
That said, this is a great forum, and if you weren't here with your input at times, it'd be dead pretty fast I think.
Roadburner wrote he he checked the oil when he got to Hilton Head, which was after he hit the pothole. Would have noticed if cap was off.
Mine: 1995 318ti Club Sport-2020 C43-1996 Speed Triple Challenge Cup Replica
Wife's: 2021 Sahara 4xe
Son's: 2018 330i xDrive
Cardoc, there's no question that, from a technical expertise, you're the guy I'd want working on my car. You are methodical in your approach, and thorough in your analysis.
Having said that, and I sincerely say this with the utmost respect for you, you're not the only guy out there that can fix cars. Lighten up a bit, or one day you're going to wake up dead from all the self-imposed stress.
One last comment... Baiting a fellow poster is anything but professional. Just as you would have me tell a tech he was mistaken in the way he was doing something (when there's no question he's in the wrong) so that he could learn from the experience, don't you think turn-around is fair play?
Just sayin'...
You're grasping at straws trying to defend a screw up by the Tire Kingdom. Yeah, maybe it was a pothole. Then again, maybe it was the tooth fairy!
He thought that he knew enough about why the check engine light came on to view himself as competent, but when really challenged didn't even know where to start. In a shop setting, that gap in knowledge would have him be no better than the tech he claims made a mistake and called an idiot. Assuming he is guessing correctly, the tech was still no more of an idiot than RB would be for not being able to explain the exact perameters that went into play for the PCM to command the MIL. Yea, I have to be a B#$D to put that much pressure on him, but what do you think it is like in the shop when something like this goes down? That's what its like being a tech and we would get told, if we can't stand the heat get out of the kitchen .
When I teach ODBII fuel trim diagnostics and repairs, and what it takes to get a car ready for emissions testing, with some failures I instruct the techs to not clear the codes. We make the correct repair and then I show them how to get the car ready to pass the emissions test by simply getting the car to pass the test that had been failing and then the car turns off the MIL on its own. That saves time and money for the shop and the consumer. But other failures make more sense to clear the codes, reset the memory and start from fresh because they will take too long to clear and running all of the monitors make more sense time wise. A fuel control issue is one of those examples. Trying to wait for the system to self clear when you have had a problem such as a lean engine is a condition is better addressed by clearing the codes because of what the system has to do to make sure that the O2's are operating correctly, and then begin the relearning process. In short, the light doesn't just go right out and many functions are blocked by the presence of the lean code.
In this trade, a tech can be right more than 99% of the time but the one time he/she falters for any reason they are an idiot in RB's eyes. I want him to know how that feels.
And, WHY would a tire guy remove an oil car? For what possible reason?
"If you are in Kansas, and you hear hoofbeats, think 'horses', not 'zebras'.
Beautiful day, put the top down and drove it (with expired tabs) around long enough to get it
good and warmed up, drove to the emission testing place praying my CEL wouldn't come on and it didn't!
Passed with flying colors! AMAZING!!
Since it's a 1991, it has to be tested on the rollers.
BTW, What do you call the person who graduated last in their class at medical school?
But back to your dictum, if it was intended to represent reality, they should be thinking cattle which makes the point that your bound to be wrong more often by guessing than you are by testing.
LOL. No it won't overload the machine, but the particulate filter will need to be changed. But there is a reason that they push thse cars through the auctions instead of drive them and its not the sound from the engine that has them do that.
The chain stores would write a tech up for not checking the fluids, belts, hoses, etc. That's how hungry they are for those $$$$. Don't sell enough? Find another place to work.
And, WHY would a tire guy remove an oil car? For what possible reason?
Now you've gone and done it, you asked the question that requires more than just speculation. In short, they wouldn't. But it seems all someone needs to do is make a story that arrives at the conclusion that they want it to and the shop/tech is at fault. No proof required.
Now, population does have something to do with it, to be sure. My county has about 881,000 people in in. Where my Mom lives, it's only around 109,000.
Oh, and the testing centers here are owned and operated by either the state or county, not sure which. So, while it may not make a station owner rich, it probably helps out a politician or two!