Check Engine light

jimzops

I will call and ask about the vacuum/exhaust leaks.
Wouldt'n any Oxygen senor problem have been detected in the diagnostics?

0patience

Yes and no.
If the O2 sensor is flat/dead/not switching, there is a possibility that it won't trip a code or it may trip a cat efficiency code, like you have.
Hard telling with Honda's systems.
But checking them with a scanner will at least show if they are switching. That will determine whether or not they are working or not.

Not sure if I can explain this right, but.....
If the O2 sensors are showing that they are switching on the scanner, then they should trip an O2 code if they are switching out of range. If they are showing flat, not switching, then they probably won't trip an O2 fault code.
Theoretically.

jimzops

Well, this morning driving on the highway, the 'check engine' light suddenly disappeared,
after being on for about 10 days.

The car is running normal (gas mileage has not changed form before/during the
engine light was on).

The shop that ran the diagnostics (revealing code 67-1) recommended I change the catalytic coverter , which I was going to do next month.

What's up with the light going out?
Is is common for the light to be on 10 days and then go out?

Confusing?

oldfarmer50

We put my son's 20 years old K-car on the road today. It runs pretty good for 133K miles except for some valve noise.
He tells me that the check engine light came on when he got it above 55mph. When he came home to ask me about it he turned off the motor. The light was not on when he re started. I told him not to worry too much and sent him on his way.

Now I'm wondering, what would cause the light to go on at 55+ and then go off when the car is re started? I drove it for a few miles at no more than 45 and never saw the light.

0patience

Tons of things could cause the light to come on.
You need to pull the troublecodes to find out where to start looking.

oldfarmer50

"...Tons of things could cause the light to come on..."

Yea, that's what I'm worried about, that this beast has tons of things that need work. :lemon:

I think someone a while back said Autozone would pull the codes for free. Does any other national chain do the same?

0patience

Quite a few of the chain parts stores will pull the troublecodes.
I would call around to your local parts stores to see who will.

jimzops

Well it has been a week and the light has not come back on. The car is running normally.
0patience, any explanation??

0patience

Since it is an emissions code, any number of things could have cause the code to trip.
Bad fuel, vacuum or exhaust leak, slow switching O2 sensor or even temperature and driving conditions can play a role in it.

That is one example of why we generally check the codes, write down the information we get, then clear the codes and road test the vehicle under conditions that best match the customer's complaint.
Sometimes, the symptom does not duplicate itself and the customer may go 6 months before it turns the light on again.

tripp5

I have a check engine light along with "emissions workshop" caption that illuminates each time I start the car. I had a shop pull the fixit code: PO 674; unfortunately they tell me that VW has not released the tracking info on this code yet. Does anybody know how I might track this code down on the cheap without a visit to the dealer?

0patience

P0674 #4 cylinder glow plug circuit.
Check the wiring to the glow plug, make sure it is plugged in and the wiring is intact.
Are the glow plugs acting funny on your vehicle?

tripp5

the car runs fine and starts right up.
I haven't checked the wiring yet; I recently broke my foot so it's a little hard for me to diagnose under the hood right now.
thanks for the tip on the code PO674; the dealer confirmed this also. He said that the glow plugs go out all the time, do you agree?
I'm new to working on diesel, are glow plugs situated similar to spark plugs on a gasoline engine?

0patience

Glow plugs are similar to spark plugs in that they will eventually burn themselves out.

Imagine the glow plug like a stove burner. Apply power to it, it heats up. Unlike a stove burner, you pressurize the atmosphere around it and throw fuel on it, then cool it down, then heat it up over and over.
Eventually, it burns itself out.

Generally, they start to fail around 80k miles or so.
But, I have seen them fail at 40k miles or go as long as 200k miles. Depends on a lot of things.

One thing to remember. Once one fails, the others are not too far behind. But at about $30 each, only replace them if you have tested them.

If you can get to the connector to the glow plug, remove the connector and us a digital Volt/ohm meter (DVOM) and check the ohms from the tip of the glow plug to ground.
You should have good continuity to ground.
Another way you can test them is to connect a test light ground clamp to the top of the glow plug, the other end of the test light into the connector for the glow plug, turn the key to ON (NOT start) and see if the test light lights up. If it does, then the glow plug can be considered operational.

tripp5

hey, thanks so much for the info.
do I need to buy the glow plug from a dealer, or are they available online? If so, can you recommend a site. Also can you recommend a good service manual for the passat diesel?

fawlty317

i recently bought a 96 sunfire and i done know much about it yet but the check engine light recently came on, it could be the sensor thats in the manifold, i had to heat up a bolt to try and get it out and i may have fried the sensor too. my question is would that sensor cause the car to idle rough at low rpms? it seems like its running way too rich now, theres a bit of black smoke that comes out and a little bit of black flecks. i know its not oil though. when i rev it high it smooths out but even when cruising on the highway at lower rpms it will run a bit rough, but downshifting and gunning it clears it right up. anyways might that be the problem or something else? any help would be great

0patience

hmm, thought I replied to this one.
Guess not.

Glow plugs are available from most parts stores.
As for manuals, I favor AlldataDIY for information, but I am biased towards them.

You can also get service information for the VW from http://www.bentleypublishers.com/volkswagen/index.htm

mbroadway

I have the same problem with my 95 model. What did you have to do to fix it. Please let me know if you can remember. Thank you
Michael

mmtiger2

I left the headlights on and the battery went dead. I jump-started it and the car would start and then shut off again. I started it and revved it for a minute in the hope of charging the battery faster. I started smelling a bit of burning smell. The car finally was able to idle on its own. When I drove it, it would shutter past 1500RPM which allowed me to drive at 15MPH. I changed the battery but the sputtering and check Engine light in on and still can't get past 15MPH. Do these cars have a rev limiter? Any ideas what I might have broken?

Mr_Shiftright

I wonder if you damaged the alternator. In hindsight, one should never try to charge a completely dead battery using the alternator--it puts it under tremendous stress.

If the alternator is now not working, your car's computer will not operate with insufficient voltage.

kjm4

A few weeks ago my check engine came on while idling and stayed on. My local mechanic said the code was a small leak in the evap system. He turned it off and told me to go through a drive cycle. I did and the light came back on. Replaced my gas cap and this time turned off the light by disconnecting the battery. Now when I turn the accessory on with the ignition key, the check engine light blinks 10 times. Does this mean I still have the evap problem and I just haven't gone through another drive cycle? Is there a way to know for sure that I fixed the problem before bringing my car in for inspection other than paying $100.00 for the smoke test? I am hesitant to keep driving just to finish a cycle because I'm afraid of being pulled over with expired stickers. Also, do I have to finish the cycle in order for the inspection computer to show that I don't have a problem assuming the gas cap did fix it?

ray80

Is the CE light now off when vehicle is running, and how long has it been off? Also what make model and year of vehicle?

nmerrill

My toyota sienna xle has 110000 miles on it. I had to replace the engine at 82000 because of my fault. Since then the check engine light comes on periodically but has gone out. Car has run fine until recently. The check engine light is always on, my mileage is decreasing and I notice the engine reving when at a stop (this would explain the decrease in mileage). When I had taken it to Toyota year ago they could not figure it out after 3 hours. But they reset it and it did not come back on for almost a year. My mechanic is at a loss trying to figure out what to do next with this code. I am not anxious to take it back to Toyota after last time but if I had a clue what it might be then I would feel better prepared.
Anyone have an idea about this code, decreasing gas mileage and engine revving?
Thanks

user777

FWIW: Googling P1350, i've seen these descriptions:

Ignition Control System
Variable Valve Timing/CMP Sensor Range/Performance
VVT Sensor Circuit Malfunction (Bank 2)
VVT (Variable Valve Timing) Sensor/Camshaft Position Sensor Circ. Malfunction (Bank2)

Fun huh?

The last was from a Lexus site if I remember correctly. Perhaps CMP stands for CaMshaft Position, and perhaps your mileage is decreasing because the vehicle is having periodic trouble determining when a given piston is TDC for regulating timing (Fuel Injection and Spark)...

But. I'm WAGing this.

Maybe the camshaft position sensor wiring is faulty, connector loose, it's not firmly mounted, it's gapped / installed wrong, or it's failing.

I would call another independant dealing specifically with Toyota/Lexus and tel them the code and ask what they come up with.

nmerrill

Thanks for the input. I'll run it by my mechanic and also try a different Toyota shop to see if they can at least direct me in the right direction. I want to fix it but don't want to keep replacing things and not correct it. nm

user777

OK, sounds like a plan. FWIW, I think I got the "Cam Position Sensor" description / purpose a bit messed up. The cam-shaft I believe schedules the valves to open and close, but the cam position sensor does not detect a piston at Top Dead Center (TDC). That would probably be another sensor, like a Crankshaft position sensor.

The Crankshaft position and pistons relative to it are fixed, but as I understand it, in a variable valve design engine, something modifies the valve opening and closing with respect to the camshaft position, otherwise the valve timing would be fixed too right?

Well, I better not write any more because I'm outside my league.

It's funny there's not more written up on this particular code found on the web. I suspect toyota's service shop manual has something on it, so i'm thinking, maybe the person you are taking it to doesn't have the best OEM references, but who's to know?

Good luck.

denham

Note: I would change the spark plugs and spark plug wires first, and if the light keeps
coming on I would check the EGR. 130,000 miles the spark plug wires should have been replaced?

nmerrill

Thanks, i appreciate the extra info. I have seen a couple of different things that might be worth trying. If I am successful, I will post it for others. I have always liked to Toyota but when there is a problem, I am not impressed with Toyota.

sgleason

About 4 months ago my check engine light came on with this code. I had my local Honda dealer replace the EGR valve. Now the check engine light is back on and giving the same code p 1491. Service manager said it was okay to drive until after the holidays. What sort of problem should I expect when I take the vehicle in for repair?

autodr

Huh??? You are kidding right? When was this? The 80's emission light?

Sorry buddy, but that is simply not true. I think you are mistaking the inertia fuel cut off switch. If you are in a wreck, the impact jars that switch to shut the fuel pump off. That way, the pump is not likely to be supplying fuel to a leaking fuel line from the wreck.

marc1973

Hi,
My 1999 Ford Expedition recently stopped blowing out any heat. Blower blows fine, but not enough heat. Brought it to a local shop and they replaced the thermostat. Picked up the truck and bearly any heat and truck runs rough. Check engine light came on half way home. Brought it right back to shop and they said that it takes the thermostat awhile to "open" up and that I probably need new spark plugs. Truck ran smoothly when I brought it in. Spark plugs were changed at approx. 90,000 miles. Could the shop have disrupted anything or caused the truck to misfire and engine light to come on. Computer check said something about cylinder #7 misfire, but something seems weird. Please advise.

tony12345

Let me get this right. Correct me if I'm wrong OK. Your truck was running fine (except for the "heat" problem right) before the service was done on it, correct. After the shop changed the thermostat, now the "Engine" light is on and there is a misfire. Here are some steps you may want to take:
1. Ask what kind of thermostat they installed? What temp thermostat they installed ? For example, 180, 195, 215 degree thermostat.

2. The next question you should ask: what is the name brand thermostat they have installed? Is the thermostat a dealer part or is it an after-market part? Believe me, it does make a difference. After market parts are know to be bad (defective) right-out-of-the-box even though the part is brand new. Once I bought a gas filter (made in China) from an autoparts store only to find that the gas filter was leaking around the seam. Next, check the anti-freeze level to make sure there is enough fluid in the reserve bottle. If the person or shop changed the thermostat, then the antifreeze level should be "topped-off" with new (clean) antifreeze. If not, then you know that the repair was not done right in the first place. If everything checks "Ok" up till this point, then take your truck back to the shop and tell them to fix it again because you paid but they did not fix the truck right the first time. You get what I am getting at right. It's like taking your car to get the oil change and after paying for this service you find out that the repair shop did not change the oil. So, give the shop the option of either do the job you originally paid for or refund you every penny you paid for the service. If the shop does not do or refuses to do one of these option, then you should sue them in small claims court. Before you storm out of the repair shop angry, just let them know that you will take them to court.

3. Next, remove and check a few spark plugs. Not just 1 or 2. Remove about 4 plugs and make sure you remove the # 7 cylinder spark plug also. If the plugs are "all" good, then have a pro test the ignition coil for cylinder # 7. Before I continue, I am assuming that your trunk has a V8 and also has 8 ignition coils for each cylinder on top of each spark plugs. These type of coils are called COP, which stands for Coil Over Plug. Switch the coil for #7 with another different cylinder (it really does not matter which one) and see if the problem changes to that new cylinder. See if the problem swaps from one cylinder to the next. If so, then you know for a fact that the coil is bad. Just make sure which coil is bad and that you do not "mix up" the coils. Good luck and keep me posted. Tony.

fco

2001alero this check engine light came on ,the car runs fine, any ideas what to expect?what may need repairing ?is a v6 engine thanks for any info

0patience

Most large brand auto parts stores will scan the codes for you.

DO NOT buy anything until you have confirmed what the codes mean.
Get the vehicle scanned and let us know what codes you get.

It could be anything from a loose gas cap, bad O2 sensor to a broekn wire.
Hard to tell without the codes. Anyone guessing is pure speculation.

ivica

My CEL light came on a couple of days ago. I jumpered terminals 8 and 13 on the data link connector as shown in the Haynes manual.

1. I obtained 6 long flashes followed by 7 short flashed (= light flash code 67) or trouble code P0420 which is catalyst system inefficiency below threshold.

Is the CEL an absolute check of the system, ie should I order a new catalytic converter from Majestic Honda?

This week I already order a muffler from them since mine is starting to have some holes and is ready to be change due to leaks and noise.

Could my CEL light be coming on as a result of my muffler back pressure change?

2. The second code I pulled from the CEL is a 7 long flashes = throttle position sensor. This CEL came on about a year ago and then turned it's self off. Can I ignore this second CEL?

Thanks

0patience

Before you replace anything, clear the codes and road test.

Do the ECM/PCM Reset Procedure.
Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on.
Test-drive 40 - 55 mph (64-88 kph) for approx. two minutes . Then decelerate for at least 3 seconds with the throttle completely closed. Then reduce the vehicle speed to 35 mph (56 kph) , and try to hold it until the scan tool indicates FAIL or PASS as the TWC test result. Is the test result FAIL? YES-Check the three way catalytic converter (TWC). NO-Intermittent failure, system is OK at this time.

As for the throttle position sensor. It may have a bad spot in it that is causing the fault.

You really need a scanner, cause pulling the fault codes the way you are doing isn't real accurate. The 7 you got for the TPS can mean 3 different things.

Clear the codes and then see how it goes. If they come back, then check the cat.

ivica

Thank you very much Opatience! I will go an pull the fuse to reset the codes. If they come back then I'll have to take it in since I don't have a scan tool or any training even if I were to purchase one.

Regards

John

0patience

One thing. If the cat efficiency code comes back, be sure to check ALL vacuum lines, and exhaust to make sure everything is ok.

Here is an article on cat efficiency.
http://www.troublecodes.net/articles/catfailure/

You mentioned a muffler problem. I would correct that before condemning the cat.

Everything, O2 sensor, fuel pressure, vacuum, exhaust pressure can affect the cat efficiency.
The only way to check to see if the cat is plugged or partially plugged is a back pressure test.

Here is an article on how to do that.
http://www.troublecodes.net/articles/jds/
Ignore the manufacturer of the tester, they are no longer in business.

pooey79

my friends mom has a 2001 chrysler sebring convertable with a 2.7 liter dohc 24valve motor and a automatic transmission... the problem is it wont shift into gear it has four trouble codes the are bein sent to my obd2 reader but we bought the book for the car but the codes aren't in the book... can somebody tell me what these codes are cause i cant find them anywhere? these are the codes P0740,P0736,P0734,and P0732

0patience

Is the transmission fluid level full?
How does the fluid look? burnt?
When was the transmission last serviced?
Are all fuses good?
It is a good probability that one of the shift solenoids is stuck in the valve body.

P0732-GEAR RATIO ERROR IN 2ND
When Monitored and Set Condition:
P0732-GEAR RATIO ERROR IN 2ND

P0734-GEAR RATIO ERROR IN 4TH
When Monitored and Set Condition:
P0734-GEAR RATIO ERROR IN 4TH

P0736-GEAR RATIO ERROR IN REVERSE
When Monitored and Set Condition:
P0736-GEAR RATIO ERROR IN REVERSE

P0740-TORQUE CONVERTER CLUTCH CONTROL CIRCUIT
When Monitored and Set Condition:
P0740-TORQUE CONVERTER CLUTCH CONTROL CIRCUIT

ivica

I have an appointment tomorrow morning at the Honda Dealer. They will diagnose the problem. Based on their recommendation I will be changing the Catalytic Converter if required.

They gave me a quote over the phone for a new Catalytic Converter, original honda part for $1000 +, or an after market for less, but he didn't indicate how much less.

Once they diagnose and tell me actual problem, I'm in a position to repair at Honda or buy the Catalytic converter at Majestic Honda for $384 + taxes and shipping and then pay the local muffler shop $80 to install.

Am I on the right track?

Regards

ivica

Opatience, thanks for your help.

I did clear the codes as you indicated after the new muffler was installed 2 days ago. The CEL keeps coming back and it's pointing to "Catalytic operation below threshold".

Once Honda does a diagnosis, I'm assuming they have equipment that will indicate 100% that it is the Catalytic converter or something else?

I.

windsongs1

I am glad I found this site. Learning a lot about the idiot lights.

I have a 2002 Corolla. In August 2007, the yellow CEL came on the night before I had to drive back to San Diego from Oakland, CA. It was drizzling. I took the car to a mechanic and was told that I need to replace the catalytic converter, but he couldn't get the parts until Monday (two days later). He assured me that it was safe to drive back to SD and cleared the code. I paid him $35. Drove back to SD without incident. In October, I finally took the car to have the catalytic converter replaced.

The 2nd mechanic asked me why I thought I needed to have the catalytic converter replaced. He asked me what the code was which I did not have. After learning the car only had about 90,000 miles, this mechanic said it could not be the catalytic converter as they last at least 200,000 miles. He hooked the car up to the analyzer but no code came up. He told me to bring the car back if the CEL comes on again.

In November, I took the car to the dealer for the 90,000 mile maintenance. The car was fine. Paid $350 for routine maintenance stuff. They hooked the car up to the analyzer too, and again, no code came up. Two weeks ago, the solid yellow CEL came on, again, in Oakland. It was also drizzling. I added one quart of motor oil and have been driving the car with the CEL on, but I worry that it may make matters worse by ignoring it.

The dealer charges $90 and 1st mechanic charged me $35 just to check it out. Worse yet, I don’t want to pay hundreds of dollars to have the wrong part replaced. After this experience, how do I know whatever the next mechanic tells me is the right thing to do? After reading all the helpful postings from the Internet, I cleaned the gas cap, making sure it was straight and tight, filled the gas tank, but solid CEL is still on. I called Kragen to see if they can pull the code for me, but they only sell the scanners.

Today, I checked all the fluid levels, and inspected the hoses under the hood. Took the car to Autozone. Was told that they are not allowed to retrieve the code in California any more. But could loan the scanner and instruct me to do it myself. The code was P0420, readout says: Catalytic converter low efficiency threshold. The car has only 95,000 miles on it. Now I just don't know what to do any more.

Both times, the CEL came on in Oakland when it was cold and drizzling. Could rainy days and high humidity cause the light to come on? I also have a tendency to drive until the gasoline level is near empty before filling the tank, and the car burns oil (I noticed it when it had only 45,000 miles). Could these things trigger the CE light (but they didn't before)? Is there a red check engine light?

The dealer told me that for the 2002 Corolla, it is within spec. even if it burns as much as one quart per thousand miles. So I have been using 20/50 weight motor oil, and it seems to burn less.

There is another unrelated problem with the car. I hear high pitched squeaking sounds when the car starts up in the morning but goes away in 30 seconds or so. It is coming from the front left side of the car, near be the belts. Could it be the belts or pulleys in the alternator or water pump, etc? Any other ideas?

Greatly appreciate any comments or insights you may have.

0patience

My suggestion would be to purchase this unit.
http://www.scangauge.com/
Scan Gauge2
About $170 and well worth the money.

I am doing a review article on this unit right now and it allows you to pull the trouble codes and clear them, plus monitor a host of things on your engine.

That way, you can check the trouble codes when the light comes on and let us know what the trouble codes are.

Without the trouble codes, we can't even begin to guess what the problem is.

ivica

The dealership confirmed today that my catalytic converter was bad. They scanned the system and found that the two Oxygen sensors were following each other, apparently the converter is not doing much and they suggested that it be changed. At the same time they suggested the change out of the pipe before the converter. I ordered all of the parts today from Majestic including a new oxygen sensor for the converter. It was suggested that it probably be a good idea to change since it was in service for 10 years and it would likely get damaged during removal.

I.

fco

hi again the check engine light went off by itself and still of thanks for your info anyway

wwest

Why not, with initial but light braking, only apply pressure to the rear brake system...?

Now that most vehicles have an ABS/VSC brake pressure/flow electric solenoid valve system wherein the front brakes can be kept from actuating, why not ALWAYS have only "drag" braking initially? Anyway only as long as only light braking is required?

"Drag" braking can be a GREAT aid in adverse, slippery roadbed conditions, and seemingly no detriment otherwise. The instant a certain braking "high" threshold is reached the front brakes are brought on-line.

Might even help to even out the wear rate of the front and rear brake pads and thereby provide an economic advantage to the owners.

channel121

I loved honda. Had an old civic. Said I would never buy anything else. No real problems. But this Accord coupe has been more trouble and $$$ then I could ever imagine. I want some advice on when to just sell it. It has 100K, last year I had transmission replaced(warranty), timing belt replaced(this is normal I know), and rear struts. All normal maintenance done. And feedback from here in the forums guided me most of the way!

As of today: It had a high pitch noise in the rear for a couple weeks and I planned to take it in when I got the $$$. Then came the Check engine light Saturday night. It is now parked. My mechanic is going to look at it Wednesday and I'm driving a rental. I plan on getting the code checked at Auto Zone this afternoon, just to see if it the transmission If so it goes right back to Honda dealership under warranty. In the past month one time it was slow to start (battery new) after it sat a few days.

When do you cut your losses? I realize I had two major and somewhat normal repairs last year and in all spent over 2K. I just worry that this may be another $3-500 (or more!) repair. Am I expecting too much?

0patience

To be honest, without knowing what the trouble codes are, it is really hard to tell what could be the problem.

Once you get the trouble codes, let us know what they are and we can help you zero in on the possible things it could be.

channel121

Autozone code says its a bad oxygen sensor. Evidently its the cheaper one to replace. Its is the on the top of the engine. Guy said about $150 to fix. I left code in at home---will post if iget a chance.

0patience

No, no, no.
Do not let them sell you anything without knowing for sure that is the problem.

To explain trouble codes to you and how they work.
No trouble code tells you to replace anything. When you get a trouble code or fault code, it is defined usually as the circuit.
So, a trouble code that says Oxygen sensor, means the oxygen sensor.
Add to the fact that there are 7 different trouble codes for the oxygen sensor alone.
Each trouble code means a different thing.
From low voltage, to high voltage to Oxygen sensor heater malfunction.

So to say that it is an Oxygen sensor code, is pretty vague.
We need to know the EXACT code to help you.