The scan only identifies the circuit being affected. It is telling you that the 02 sensor isn't happy, not that it's bad. No diagnostic system for cars is yet good enough to identify the actual component malfunctioning.
I'd be more inclinded to test your ignition and/or #7 injector circuit.
I think you can check injector pulse with a noid light. I'm not sure how your car's ignition system is set up, whether you have coil packs or what....a misfire will irritate your 02 sensor but the cause of the misfire can be elusive sometimes. I'm sure that with the right info and a voltmeter you can do wonders but I don't have the talent to tell you how on your car without doing homework.
Hi I have a 2001 Honda Civic Lx and I bought it used from the dealer in 2002. At 30 k the Maint Req'd came on but the car kept running smooth. Now at 90,000 the check engine light comes on and off. And the Maint Req'd still on. I have changed the o2 sensor the spark plugs, wires, air filter always changing the oil etc. but as soon as the light pops on my gas mileage gets worse, what can I do to fix these problems
My saturn has a high idle and a misfire on cylinder one. I would like more info on what can be causing this. We have replaced the spark plugs, the spark plug wires, the ignition coil, the throttle position sensor, and did a compression test on the cylinders...all were good. Now I want to know if it could be a timing sensor in the computer and can we replace that ourselves or is this something that Saturn will rip me off for again???? Please help!!!! :sick:
Dodge Dakota Truck- Quad-Cab 2000 In cold, rainy weather I receive “Check Engine Light” on Diag and advise. Technician found Medium Evap leak but code not active. Suspect intermittent failure of the leak detection pump but without code active or leak present. Is this, perhaps, computer or computer program problem? Happened this problem often in Dodge-Dakotas-2000? Please give me a hint! ">
I own a 95 Nissan Maxima with about 150,000 miles on it. Recently the check engine light came on, and when i took it to the dealership they told me that the car has an issue with its EGR sensor, and that carbon is backing up. Also said that there is a problem with the oxygen sensors. All this is gonna cost they said about $2000, which is out of the question. I'm just wondering, does anyone know what is the worst that can happen if we just ignore these problems and drive the car without fixing it.
I have a 2000 neon and the check engine light keeps coming on. I have had no problems in the past at all with this car. The car begins to shudder and shake as if it is going to die. It doesn't seem to matter if it is at a high speed or not. The diagnostic code 304 shows a misfire. What could be causing this to happen? The coil pack has been checked and it is fine. They have now put a gas sensor? on it. On the last oil change I also noticed there were very fine threads of metal. Could these things be related? I have 150,000 kms on it. Help!!!
This problem sounds like the same one I have had with my '96 Maxima. Although my check engine light does not work I have not been able to pass inspection because my car has failed for the oxygen sensor, the EGR flow, knock sensor, and evaporation valve. The estimate on mine was also $2,000. I have driven it for a year and a half without fixing it... gotten a couple of tickets for the Rejection sticker. I would really like to get mine fixed... if you find an answer let me know!!!!
Engine light has been on for 3 days, pulled battery cable engine light came back on, Went to Advance Auto Parts,in PA Their Global OBDII gave me two codes, P1166 and P1167, Fuel Air Metering. This is for a 2002 Honda CRV. Could you tell me what components are involved? Thanks.
i have an 01 silverado with a 4.8 liter engine.about six months ago my truck was showing a multiple cylinder misfire.so i replaced the plugs and wires.it ran fine for a week and started doing that again.so i replaced them again.the misfiring stopped but my truck started surging and everytime i try to kick in the passing gear,it surge's and cuts out.ive replaced everything in the fuel system from the pump to the regulator.ive replaced an o2 sensor and the crankshaft sensor.which now it is showing the code p0336,saying that sensor is sending an incorrect signal for up to three seconds.i have spent over a thousand dollars trying to fix this problem.if anyone can help me out,please let me know. thanks
I've got a 2001 Toyota Corolla. Recently, the check engine light has been coming on. I've taken it to both the dealer and to another repair place and both told me that it was a problem with a leak from the evaporation system and that it was usually caused by a loose gas cap. The dealer replaced the gas cap and I've made sure it's on tight, but the check engine light has come on for the 3rd time. I'm getting really frustrated. Is this something that I have to worry about and what do I have to do to get it properly fixed?
I purchased a 97 Honda Civic LX, with a engine/transmission/catalytic converter contingency. The check engine light is on, and I had Autozone read the codes. It came up with P0450 (Malfunction in electrical circuit for pressure sensor in evaporative emission control system), P0453 (High voltage), P1508, and P1259.
What are P1508 and P1259, and what could possibly be causing these problems. The cars idle is horrible. It constantly goes up and down...
if it was me i would look into that injector for that cyclinder and for vaccum leaks around the intake use a can of 2+2 to spray around the intake and vaccum hoses
does the engine run rough or smooth spray a little 2+2 in intake does it smooth out if rough
disconnect injector does engine idle down a little if runs rough and it has no change when disconnect injector sound like clogged injector
possible bad fuel preasure regulator if smell raw gas pull plug does it smell like gas
I have a 92 Buick Regal with 100,000 miles. I was driving to work this morning and the “Check Engine” light came on. I then noticed the voltage gauge on the dash board was showing close to 18 volts. Any ideas, have you seen this before? New battery?
Help! My baby has only just broken 80k miles and the guy at the shop says "he can't fix it--no parts avail for the 'air/fuel mixture' system available anywhere"... Quik history: I have mostly driven this car for short distances--just long enough for the Turbo to get nice and warm, then shut it off...apparently hard on it...only recently was told to let it idle 1 min. b/4 shutoff, but not why...16 year old car..first time I'd heard it... I've had "loss of power" problems ever since I hit a huge pothole within 6 mos of purchase of this car...no one I took it to for repair ever could find anything wrong with it...nor could the "surging" trouble be located/fixed by anyone...I think I saw something about problems like this with this model that I suspect may be design flaw but not being a mechanic, and having scanned 100 or so VERY OLD postings on this site, can't be too sure about that...I had the "O2 sensor" replaced less than a year ago which fixed the surging problem. Now, after letting the car sit (w/o starting it up for aprx 2 wks when I was very ill), with it having a little less than 1/4 tank of gas in it, from the first time I started it up, I had trouble getting it to start--kept trying to die--but I found that if I kept giving it gas, it would eventually "warm up" and run ok...that lasted a few days and I only took short trips... Then, I got paid, so I could afford to finally fill up the tank, figuring that I'd probably released some 'low gas tank scum' into it, but that it would be okay with more gas in it, and that driving it I could blow out any carbon residue...but...then...the Check Engine Light came on...and went off...I read the manual, and it said something like "...it was an indication of fuel emmissions not meeting mfg standards, take car to dealer.." Yeah, right! Dealerships have, in the past, omitted info I needed, not been able to fix it, and bent me over in the process without so much as the HINT of a kiss...I knew I would have to find a trust-able mechanic, since the car was also losing power/not accelerating till after warmed up for quite a few minutes...but before I could do that... I tried to make an emergent midnite run after my kid...I made it only a few blocks, when it just REFUSED to accelerate, the check engine light came/stayed on and finally had to turn around with it going maybe 10 mph, coughing/choking/gaging/backfiring the mile or so home...AAAARRGGHHH! My baby's really sick...HAVE there ever been any recalls on anything related to what could have happened? After reading postings, sure seems there should have been!! Or did I just get a lemon?!?">
In TN I have to pass the emssions test with a clean check engine light. I got it to go off but it came up that I didnt complete the drive cycle. But when I do it comes back on. I have a few codes coming up but I want to know how to pass the emissions with out having to fix what is needed right away...does anyone know how to bypass that?
2000 nissan sentra with only 54k. what are symptoms a bad oxygen sensor. my check engine light was on recently, i got my oil changed cause i was about 2k over..... i had gotten my car scanned and they said possibly oxy. sens but 30 min. after i left the light went off. i noticed that when i dog... so to speak the clutch that some smoke comes from the exhaust. is this a symptom of the oxy. sens. thank you in advance.
the system and process are designed so that you fix the root cause of the problem. if there were a simple way of defeating the system, many people would do so, probably leading to increased emissions but also potentially subsequent and more expensive engine damage.
if you know the codes, you can research them. you can consult a dealer or local shop specializing in your car and estimate what it would cost to get the system cleared.
I have a 2001 Nissan Pathfinder with 81,000 miles & I have replace 2 of the 4 oxygen sensors. Take your car to Autozone & have them pull the trouble codes for free. Get the 4 digit codes. What color is the smoke coming from the exhaust?
(also posted in the Ford Excort Wagon forum) I have a 1999 Ford XL (lx) wagon. I've been very happy with the car. About a year ago the speedometer started to go up and down on its own every now and then. I had the oil changed at a Jiffy Lube - all we have out here anymore - and the speedometer/odometer stopped working completely. At the same time the service engine soon light came on. Naturally Jiffy Lube could find nothing wrong when I took it back. I've lived in the rural area all of my life. I drive the same roads, etc. and have no problem without the speedometer. In NY all cars have to have this light off to pass inspection. Mine's due next month. I ordered the manual, have browsed here and there, but cannot find anywhere that gives me a hint as to how to turn this light off. I don't know anything about cars, and have no male friends or relatives that do either apparently. If I take it to a local dealer for the computer checkup it's $300 just to run the engine through the computer, any repair of the speedometer is extra. My car has well over 100,000 miles on it and I have no intention of ever selling it so the speedometer/odometer thing doesn't bother me. Can anyone give me a clue? Please? Like most people, I don't have the extra 3-5 hundred to throw at a problem that isn't a problem. Thanks so much.
In my 04 Jeep Grand Cherokee the check engine light flashes on and off when the key is in the on position, before the car is started. Can somebody please help and tell me what this could mean? Before it stayed on when it does the light test, now it flashes. It does not come on while driving only when the key is turned to the on position. I Really Need Help! Thank You Very Much
you have to get the light reset using a scan tool, an OBD-II device that hooks to the computer network in the vehicle and allows one to pull codes (which can be done by an auto parts store like AutoZone or NAPA Parts or other).
You can reset the light, but if the condition is continuous, it will come back on. If it doesn't there is another hurdle... when you reset the light, you must drive the vehicle a certain amount before the computer will indicate "ready" to the inspection station's computer. If it stays off and readies itself, you will probably pass. If it readies itself and comes back on, sooner or later you're looking at a repair bill.
Perhaps you want to consult a mechanic/station that services Fords. The $300 for a checkup seems steep. Perhaps an independant shop will be more willing to work with you, but like I said, you probably can get the codes read for free at a parts store then google the heck out of them.
maybe, just maybe the code is for something trivial that the independant shop can quickly repair without killing you.
hello, did the other key make the light turn off? The p1259 immobilizer to pcm signal error code is also plaguing my girl friends 1998 honda accord 4cylinder. This additional message is included with the p1259 error "manufacturer control fuel air metering"
Could be your engine computer(ECM). There is a company that repairs engine computers and sells used or remanufactured ecm's. Here is their web address www.autocomputersupply.com
Driving my 88 Caprice home yesterday (interstate-over 90 degree day) the temp light came on. Checked the belts, fan, and coolant and all was well. The only way I could get the light to go out was run the heater. And it was consistant, turn off the heater and in a while it came on, heater on- temp light goes out. OK, my first thoughts would be thermostat not opening all the way (how do you check that?), bad radiator cap, radiator clogged and needs flushing and refil. Any other thoughts and in what order would you start?
The temperature sensor also could have shifted and be turning on earlier than it needs to compared to 18 years ago.
You actually need a temperature gauge installed temporarily to see what the coolant temp does. I suspect it's the radiator having "bloom" on the ends of the tubes from interaction with the water--like mineral buildup. A radiator shop can probably look in it quickly and tell you. Or if you do-it-yourself and the radiator has never been service, in your car it's easy to take out and carry to the shop for opinion.
Went to dealer for routine oil change lube etc and tire rotation on my 2002 Mazda Millenia with 22,000 miles. No CEL on when I brought it to the dealer. Drove out with CEL on...any ideas..Dx test said fuel meter etc..checked gas cap etc. Took back to dealer the next day.....said I may have vacuum leak need to take off the manifold cover..Is it worth to do...very expensive..what the heck happened at the dealership..
The engine system check light on my '92 Camry 6xle suddenly went on, with no obvious symptoms. After a short while the light went off, but then came on again. Perhaps a coincidence but the night before I softly back-ended another car - not hard enough to mark either car. Any chance these 2 are connected? If not, what is the best way to have it checked out. (A brief phone conversation with my mechanic said minimum $70 labor to have computer scan.)
The car has a super-charged engine. I filled gas tank once with premium grade gas. The engine light went on and the car had hesitation starts. Midas found a P0300 code and suggestted me to do transmission tube flush and tune-up, and replace a few things, but they were not sure the problem will be gone. So I went to a Mazda dealer. They think there is something wrong with feul ignition system. To fix the problem, it will cost a lot of money, they don't think it's worth it, so they don't want to open the engine to dig further. But they found I used wrong grade of gas, so they put some kind of engine cleaning fluid and let me go. The car ran almost one week without any problem. Then the engine light is on again, but no much sign of hesitation. So I drove it for two weeks and bought a bottle of engine system cleaning fluid from WalMart for a new tank refill. Two days after the refill, the check engine light is off. I was so happy and thought it will be gone forever, but the happiness only lasted for one day. The light is on again until today, almost two weeks. I'm not sure if the engine hesitation is always there. Sometimes when I start car I feel more engine vibration than other times and I saw thick smoke comes from back. This morning, I felt clear hesitations when I was driving the car. The car seems not have much power. More than that, the engine light fleshed several times and then stays on. Anyone knows what is going on? Should I let the autoshop to look at it a little more and replace all kind of things? Thanks.
P0300 is a random misfire code. Did they replace the spark plugs with OEM plugs? Did they replace the plug wires? When was the fuel filter replaced?
Also, this TSB may help. "Top Engine Cleaner" can be purchased at any GM dealer.
01-027/02 1995 - 2002 Millenia (KL engine) - MIL ILLUMINATION WITH DTC P0300 TO P0306 APPLICABLE MODEL(S)/VINs All 1995 - 2002 Millenia models with 2.5L V6 (KL) DESCRIPTION After a cold start, MIL comes on with DTC P0300 to P0306 stored in the memory. In most cases, this concern may be caused by misfire occurring in one cylinder during idle. The use of premium fuel (high-octane fuel) may be allowing carbon deposits to accumulate on the exhaust valve seat, causing momentary insufficient compression. To correct this concern, remove carbon deposits using a suitable top engine cleaner. NOTE : After removing the carbon deposits, be sure to advise the customer to use lower-octane fuel (87 or 89 octane) to help prevent future recurrences. REPAIR PROCEDURE 1. Warm up the engine until it reaches the normal operating temperature, then turn the ignition off. 2. Locate the canister purge vacuum port into the intake manifold to feed the cleaner into the engine. This allows the cleaner to distribute evenly. CAUTION: ^ Be sure to feed the "Top Engine Cleaner" into the engine through the correct vacuum port. ^ Do NOT use a PCV hose. If too much cleaner enters the engine, the engine may be damaged. ^ Do NOT use the vehicle vacuum hose. You have to prepare a new hose and fit an orifice (E5B6 13 986) into it to limit the suction rate. ^ With an orifice fitted into a new hose, about 7.5 fluid ounces will be fed into the engine, taking at least 1.5 minutes or longer. If the cleaner is fed at a faster rate than 7.5 fluid ounces per 1.5 minutes, excess liquid entering the cylinders may cause hydrolock, resulting in engine damage. 3. Fit the other end of hose into the container of "Top Engine Cleaner". 4. Choke off the hose with locking pliers (vise grips), then start the engine. NOTE : Large amounts of exhaust smoke will be emitted in the next step. Be sure to connect the exhaust evacuation hose to the tailpipe and ensure there is adequate ventilation. 5. While cycling the engine speed between 1500 and 3000 rpm: a. Remove the locking pliers from the hose with the orifice. The intake manifold vacuum will now draw the cleaner from the container. b. Monitor the feed rate. Only 7.5 fluid ounces (half can) should be fed, taking at least 1.5 minutes or longer. c. When almost 7.5 fluid ounces has been fed into the engine, reduce engine speed and allow the engine to stall. If the engine does not stall, turn the ignition off. 6. With the engine off, wait at least an hour (not more than 24 hours). This allows the cleaner to soak into the carbon deposits, increasing its effectiveness. 7. Repeat Step 1-5, using the remaining portion (approximately 7.5 fluid ounces) of the cleaner. NOTE: Do not allow the engine to stall this time. 8. Remove the hose with the orifice and reconnect the canister purge vacuum hose to the intake manifold. 9. Test drive the vehicle 3 miles or longer to completely remove the remaining liquid and carbon deposits from the engine. 10. Perform engine oil and engine oil filter replacement service. NOTE : With new engine oil and filter in the engine, start the engine, then raise the engine rpm several times to circulate the new oil throughout the engine. 11. Verify repair. NOTE : Be sure to advise customer to use lower-octane fuel (87 or 89 octane). Periodic use of a well-known gas treatment (such as Chevron Techron) can be recommended to help prevent future recurrences.
HI I HAVE A 2002 TOYOTA COROLLA. MY CHECK ENGINE LIGHT IS ON, I PUT A SCAN TOOL ON IT (P0420) (CAT EFFICIENCY BELOW THRESHOLD BANK 1) DOES THIS MEAN I NEED TO REPLACE MY 02-SENSOR THE ONE BEFORE THE CAT, OR AFTER THE CAT.
My 1993 Geo Prizm almost ran out of gas the other day and ever since it hasnt run right. It almost seems like it is only running on 3 cylinders and then my check engine light came on. Inside my car now has a strong smell of gas.I checked the light and it gave me a code 25. What could this be? Im at a loss here. Please help!
Well, code 25 actually points to a lean running condition, but you say you have a strong smell of gas...Im going to go out on a limb here and venture a theory, let's say that you have an O2 sensor that has devoloped a lean bias, or maybe become dead altogether, that in turn would drive your fuel trim positive, (adding fuel). This is how the PCM is SUPPOSED to react, but since you are not ACTUALLY running lean, the possibly bad O2 sensor just SAYS you are, you end up with a RICH condition, which in turn causes your gasses smell and rough running. I wouldn't feel to bad about saying a POSSIBLE O2 sensor at this point, -good luck-
I actually replaced the spark plugs and wires, and found that one (or possibly more) of my spark plugs were faulty, causing my car to run on only 3 cylinders instead of 4 and all that fuel that was being pumped to the faulty spark plug was firing back into the system causing the smell of gas. My airbag light is still on, but the CE light went off minutes after I replaced the plugs and wires. Any suggestion on the airbag light? Im at a loss on that one.
Dont have any advice on the airbag light, but the dead miss makes since (sorry, Im a theory junkie and like to disect these things) All though you are smelling gas, that O2 sensor see's a full cylinder of unburned AIR being pumped into the exaust, a lean code triggered by an ignition missfire, text book example of fuel control theory and it's shortcomings!! Like I said in other post, codes can only take you so far...-autojunkie-
In Toyota Corolla, there are certain sensors inputs to ECU Engine Control Unit which can trigger "Check Engine". These are....
Engine coolent Temperature sensor Mass Air flow sensor Crank shaft Position Sensor Throttle position sensor Park / nuetral gear Selector Position Vehicle Speed Sensor Knock Sensor Power steering Oil Pressure Intake Air Sensor Fule / Vapour Pressure Absolute Manifold Pressure Oxygen / Air-fuel Ratio Sensor
If you can start and steer your car well, and still Check Engine light remains on you should target last three sensors. Possible causes are: 1. Improper fuel pressure.
Leak in fuel system, may be pin-hole, To detect this fill-up your tank to the maximum, park your car in a clean space for a while 5 to 10 min. and check the for the fuel leak on the bottom, if there is any, may be because of Fuel intake pipe, Gas Tak or Fuel lines. Exhaust system leak. 2. Leak in Exhaust system. Can be detected easily. 3. Fuel injector restricted. Use Fuel Injector Cleanner.
4. Defective heated Main oxygen sensor No. 1. If you are very sure about 1,2 and 3, then target main oxygen sensor located after exhaust manifold and before catalytic convertor. Replace this with brand new one after replacement disconnect battery positive terminal for a while and reconnect it. start the car and see if Check Engine light turn on after a while replace sub oxygen sensor after catalytic convertor and before exhaust tail pipe. after replacement disconnect battery positive terminal for a while and reconnect it. start the car and see if Check Engine light turn on after a while taget following sensors in sequence.
There is a lot more than a list of sensors that can trigger a check engine light, AND this code is not a TOYOTA code, its a global OBDII code:
"HI I HAVE A 2002 TOYOTA COROLLA. MY CHECK ENGINE LIGHT IS ON, I PUT A SCAN TOOL ON IT (P0420) (CAT EFFICIENCY BELOW THRESHOLD BANK 1) DOES THIS MEAN I NEED TO REPLACE MY 02-SENSOR THE ONE BEFORE THE CAT, OR AFTER THE CAT."
A failed upstream O2 Sensor will NOT cause this code to be thrown, so there is not purpose in throwing a part at it in hopes of a diagnosis. This code is triggered when the downstream o2, matches the upstream 02 too closely. Now lets think about this rationally, this code essentially says that the rear o2 is too active, has anyone ever seen an o2 sensor fail by being too active, me either. Now to my point, the rational course of action,is to replace the CAT, check for an exhaust leak in front of the cat, behind the front 02, but if none is there, you probably need a CAT, this code is not easy to throw, BOTH o2 sensors have to pass their own monitors (test) before cat effiency is ever even considered by the ECM. Most codes are easy to falsify, and the computer often throws a bogus code based on what it sees, but this praticular code is almost always right on the money, you need a catalytic convertor to cure your light, and to pass inspection (if that applies to you)...
The mechanic I went to to check this out told me the code was #71 and that I would need to replace the EGR temperature sensor, but probably not necessary until my Smog Test comes up (in CA, once every 2 years). They told me the job would cost about $200-250. Does that sound about right?
I have just had the P0420 code occur on my 2002 Corolla (95,000 miles). I have been researching this code for awhile and was all set to replace the upstream O2 sensor until I read you post. Your logic seems solid to me and it appears you know what you are talking about.
I am curious if you know what type of self-testing is performed on the sensors before they are used for monitoring the O2 levels?
"If you can start and steer your car well, and still Check Engine light remains on you should target last three sensors." "99.9% your problem will be solved at the step 4."
*sigh* I really hate to see posts like this. Any time you generalize what could cause the check engine light to come on, you are leading folks in the wrong direction. Just like the people that say that every time the check engine light comes on, it is usually the gas cap loose.
Without knowing what the trouble codes are, NO ONE CAN GUESS! Plain and simple. To say that the O2 sensor or the gas cap is always the reason the check engine light comes on is PURE SPECULATION and most often wrong.
Now don't get me wrong, I am not trying to discount the information, but when it is wrong, it is necessary to correct it. But then again, who am I to say what information is wrong or right?
As I have stated hundreds of times and has been stated by several of my associates........... A trouble code or the check engine light on does NOT mean replace the sensor. It means that there is a problem with the CIRCUIT. Diagnose the problem BEFORE replacing ANY sensor.
Hello all, i have a 1994 Infinity G20 which I just replaced the engine. Runs great but still has check engine lite on. The local parts place scanned and got code p1400 which on the infinity code site means its the egrc/vlv problem. I replaced both parts but ligte still comes on after 20 minutes of driving....Any suggestions on the P1400 code. Thx Mike.
Comments
I'd be more inclinded to test your ignition and/or #7 injector circuit.
In cold, rainy weather I receive “Check Engine Light” on Diag and advise.
Technician found Medium Evap leak but code not active. Suspect intermittent failure of the leak detection pump but without code active or leak present.
Is this, perhaps, computer or computer program problem?
Happened this problem often in Dodge-Dakotas-2000?
Please give me a hint! ">
Ben
What are P1508 and P1259, and what could possibly be causing these problems. The cars idle is horrible. It constantly goes up and down...
Thanks for any help you can provide....
does the engine run rough or smooth spray a little
2+2 in intake does it smooth out if rough
disconnect injector does engine idle down a little
if runs rough and it has no change when disconnect
injector sound like clogged injector
possible bad fuel preasure regulator if smell raw gas
pull plug does it smell like gas
do you have spark
Quik history: I have mostly driven this car for short distances--just long enough for the Turbo to get nice and warm, then shut it off...apparently hard on it...only recently was told to let it idle 1 min. b/4 shutoff, but not why...16 year old car..first time I'd heard it...
I've had "loss of power" problems ever since I hit a huge pothole within 6 mos of purchase of this car...no one I took it to for repair ever could find anything wrong with it...nor could the "surging" trouble be located/fixed by anyone...I think I saw something about problems like this with this model that I suspect may be design flaw but not being a mechanic, and having scanned 100 or so VERY OLD postings on this site, can't be too sure about that...I had the "O2 sensor" replaced less than a year ago which fixed the surging problem. Now, after letting the car sit (w/o starting it up for aprx 2 wks when I was very ill), with it having a little less than 1/4 tank of gas in it, from the first time I started it up, I had trouble getting it to start--kept trying to die--but I found that if I kept giving it gas, it would eventually "warm up" and run ok...that lasted a few days and I only took short trips...
Then, I got paid, so I could afford to finally fill up the tank, figuring that I'd probably released some 'low gas tank scum' into it, but that it would be okay with more gas in it, and that driving it I could blow out any carbon residue...but...then...the Check Engine Light came on...and went off...I read the manual, and it said something like "...it was an indication of fuel emmissions not meeting mfg standards, take car to dealer.."
Yeah, right! Dealerships have, in the past, omitted info I needed, not been able to fix it, and bent me over in the process without so much as the HINT of a kiss...I knew I would have to find a trust-able mechanic, since the car was also losing power/not accelerating till after warmed up for quite a few minutes...but before I could do that...
I tried to make an emergent midnite run after my kid...I made it only a few blocks, when it just REFUSED to accelerate, the check engine light came/stayed on and finally had to turn around with it going maybe 10 mph, coughing/choking/gaging/backfiring the mile or so home...AAAARRGGHHH! My baby's really sick...HAVE there ever been any recalls on anything related to what could have happened? After reading postings, sure seems there should have been!! Or did I just get a lemon?!?">
if you know the codes, you can research them. you can consult a dealer or local shop specializing in your car and estimate what it would cost to get the system cleared.
I have a 1999 Ford XL (lx) wagon. I've been very happy with the car. About a year ago the speedometer started to go up and down on its own every now and then. I had the oil changed at a Jiffy Lube - all we have out here anymore - and the speedometer/odometer stopped working completely. At the same time the service engine soon light came on. Naturally Jiffy Lube could find nothing wrong when I took it back. I've lived in the rural area all of my life. I drive the same roads, etc. and have no problem without the speedometer. In NY all cars have to have this light off to pass inspection. Mine's due next month. I ordered the manual, have browsed here and there, but cannot find anywhere that gives me a hint as to how to turn this light off. I don't know anything about cars, and have no male friends or relatives that do either apparently. If I take it to a local dealer for the computer checkup it's $300 just to run the engine through the computer, any repair of the speedometer is extra. My car has well over 100,000 miles on it and I have no intention of ever selling it so the speedometer/odometer thing doesn't bother me. Can anyone give me a clue? Please? Like most people, I don't have the extra 3-5 hundred to throw at a problem that isn't a problem. Thanks so much.
You can reset the light, but if the condition is continuous, it will come back on. If it doesn't there is another hurdle... when you reset the light, you must drive the vehicle a certain amount before the computer will indicate "ready" to the inspection station's computer. If it stays off and readies itself, you will probably pass. If it readies itself and comes back on, sooner or later you're looking at a repair bill.
Perhaps you want to consult a mechanic/station that services Fords. The $300 for a checkup seems steep. Perhaps an independant shop will be more willing to work with you, but like I said, you probably can get the codes read for free at a parts store then google the heck out of them.
maybe, just maybe the code is for something trivial that the independant shop can quickly repair without killing you.
good luck.
You actually need a temperature gauge installed temporarily to see what the coolant temp does. I suspect it's the radiator having "bloom" on the ends of the tubes from interaction with the water--like mineral buildup. A radiator shop can probably look in it quickly and tell you. Or if you do-it-yourself and the radiator has never been service, in your car it's easy to take out and carry to the shop for opinion.
2014 Malibu 2LT, 2015 Cruze 2LT,
had hesitation starts. Midas found a P0300 code and suggestted me to do transmission tube flush and tune-up, and replace a few things, but they were not sure the problem will be gone. So I went to a Mazda dealer. They think there is something wrong with feul ignition system. To fix the problem, it will cost a lot of money, they don't think it's worth it, so they don't want to open the engine to dig further. But they found I used wrong grade of gas, so they put some kind of engine cleaning fluid and let me go. The car ran almost one week without any problem. Then the engine light is on again, but no much sign of hesitation. So I drove it for two weeks and bought a bottle of engine system cleaning fluid from WalMart for a new tank refill. Two days after the refill, the check engine light is off. I was so happy and thought it will be gone forever, but the happiness only lasted for one day. The light is on again until today, almost two weeks. I'm not sure if the engine hesitation is always there. Sometimes when I start car I feel more engine vibration than other times and I saw thick smoke comes from back. This morning, I felt clear hesitations when I was driving the car. The car seems not have much power. More than that, the engine light fleshed several times and then stays on. Anyone knows what is going on? Should I let the autoshop to look at it a little more and replace all kind of things? Thanks.
Did they replace the spark plugs with OEM plugs?
Did they replace the plug wires?
When was the fuel filter replaced?
Also, this TSB may help. "Top Engine Cleaner" can be purchased at any GM dealer.
01-027/02
1995 - 2002 Millenia (KL engine) - MIL ILLUMINATION WITH DTC P0300 TO P0306
APPLICABLE MODEL(S)/VINs
All 1995 - 2002 Millenia models with 2.5L V6 (KL)
DESCRIPTION
After a cold start, MIL comes on with DTC P0300 to P0306 stored in the memory. In most cases, this concern may be caused by misfire occurring in one cylinder during idle. The use of premium fuel (high-octane fuel) may be allowing carbon deposits to accumulate on the exhaust valve seat, causing momentary insufficient compression.
To correct this concern, remove carbon deposits using a suitable top engine cleaner.
NOTE : After removing the carbon deposits, be sure to advise the customer to use lower-octane fuel (87 or 89 octane) to help prevent future recurrences.
REPAIR PROCEDURE
1. Warm up the engine until it reaches the normal operating temperature, then turn the ignition off.
2. Locate the canister purge vacuum port into the intake manifold to feed the cleaner into the engine. This allows the cleaner to distribute evenly.
CAUTION: ^ Be sure to feed the "Top Engine Cleaner" into the engine through the correct vacuum port.
^ Do NOT use a PCV hose. If too much cleaner enters the engine, the engine may be damaged.
^ Do NOT use the vehicle vacuum hose. You have to prepare a new hose and fit an orifice (E5B6 13 986) into it to limit the suction rate.
^ With an orifice fitted into a new hose, about 7.5 fluid ounces will be fed into the engine, taking at least 1.5 minutes or longer. If the cleaner is fed at a faster rate than 7.5 fluid ounces per 1.5 minutes, excess liquid entering the cylinders may cause hydrolock, resulting in engine damage.
3. Fit the other end of hose into the container of "Top Engine Cleaner".
4. Choke off the hose with locking pliers (vise grips), then start the engine.
NOTE : Large amounts of exhaust smoke will be emitted in the next step. Be sure to connect the exhaust evacuation hose to the tailpipe and ensure there is adequate ventilation.
5. While cycling the engine speed between 1500 and 3000 rpm:
a. Remove the locking pliers from the hose with the orifice. The intake manifold vacuum will now draw the cleaner from the container.
b. Monitor the feed rate. Only 7.5 fluid ounces (half can) should be fed, taking at least 1.5 minutes or longer.
c. When almost 7.5 fluid ounces has been fed into the engine, reduce engine speed and allow the engine to stall. If the engine does not stall, turn the ignition off.
6. With the engine off, wait at least an hour (not more than 24 hours). This allows the cleaner to soak into the carbon deposits, increasing its effectiveness.
7. Repeat Step 1-5, using the remaining portion (approximately 7.5 fluid ounces) of the cleaner.
NOTE: Do not allow the engine to stall this time.
8. Remove the hose with the orifice and reconnect the canister purge vacuum hose to the intake manifold.
9. Test drive the vehicle 3 miles or longer to completely remove the remaining liquid and carbon deposits from the engine.
10. Perform engine oil and engine oil filter replacement service.
NOTE : With new engine oil and filter in the engine, start the engine, then raise the engine rpm several times to circulate the new oil throughout the engine.
11. Verify repair.
NOTE : Be sure to advise customer to use lower-octane fuel (87 or 89 octane). Periodic use of a well-known gas treatment (such as Chevron Techron) can be recommended to help prevent future recurrences.
The code will probably tell you one cylinder isn't firing but won't tell you why.
Engine coolent Temperature sensor
Mass Air flow sensor
Crank shaft Position Sensor
Throttle position sensor
Park / nuetral gear Selector Position
Vehicle Speed Sensor
Knock Sensor
Power steering Oil Pressure
Intake Air Sensor
Fule / Vapour Pressure
Absolute Manifold Pressure
Oxygen / Air-fuel Ratio Sensor
If you can start and steer your car well, and still Check Engine light remains on you should target last three sensors. Possible causes are:
1. Improper fuel pressure.
Leak in fuel system, may be pin-hole, To detect this fill-up your tank to the maximum, park your car in a clean space for a while 5 to 10 min. and check the for the fuel leak on the bottom, if there is any, may be because of Fuel intake pipe, Gas Tak or Fuel lines.
Exhaust system leak.
2. Leak in Exhaust system. Can be detected easily.
3. Fuel injector restricted. Use Fuel Injector Cleanner.
4. Defective heated Main oxygen sensor No. 1.
If you are very sure about 1,2 and 3, then target main oxygen sensor located after exhaust manifold and before catalytic convertor. Replace this with brand new one
after replacement disconnect battery positive terminal for a while and reconnect it. start the car and see if Check Engine light turn on after a while replace sub oxygen sensor after catalytic convertor and before exhaust tail pipe. after replacement disconnect battery positive terminal for a while and reconnect it. start the car and see if Check Engine light turn on after a while taget following sensors in sequence.
5. Defective Manifold Absolute Pressure (MAP) sensor.
6. Defective Engine Coolant Temperature (ECT) sensor.
99.9% your problem will be soved at the step 4.
GOOD LUCK!!!
"HI I HAVE A 2002 TOYOTA COROLLA. MY CHECK ENGINE LIGHT IS ON, I PUT A SCAN TOOL ON IT (P0420) (CAT EFFICIENCY BELOW THRESHOLD BANK 1) DOES THIS MEAN I NEED TO REPLACE MY 02-SENSOR THE ONE BEFORE THE CAT, OR AFTER THE CAT."
A failed upstream O2 Sensor will NOT cause this code to be thrown, so there is not purpose in throwing a part at it in hopes of a diagnosis. This code is triggered when the downstream o2, matches the upstream 02 too closely. Now lets think about this rationally, this code essentially says that the rear o2 is too active, has anyone ever seen an o2 sensor fail by being too active, me either.
Now to my point, the rational course of action,is to replace the CAT, check for an exhaust leak in front of the cat, behind the front 02, but if none is there, you probably need a CAT, this code is not easy to throw, BOTH o2 sensors have to pass their own monitors (test) before cat effiency is ever even considered by the ECM.
Most codes are easy to falsify, and the computer often throws a bogus code based on what it sees, but this praticular code is almost always right on the money, you need a catalytic convertor to cure your light, and to pass inspection (if that applies to you)...
Thanks for responding. Much appreciated!!
I have just had the P0420 code occur on my 2002 Corolla (95,000 miles). I have been researching this code for awhile and was all set to replace the upstream O2 sensor until I read you post. Your logic seems solid to me and it appears you know what you are talking about.
I am curious if you know what type of self-testing is performed on the sensors before they are used for monitoring the O2 levels?
"99.9% your problem will be solved at the step 4."
I really hate to see posts like this.
Any time you generalize what could cause the check engine light to come on, you are leading folks in the wrong direction.
Just like the people that say that every time the check engine light comes on, it is usually the gas cap loose.
Without knowing what the trouble codes are, NO ONE CAN GUESS!
Plain and simple.
To say that the O2 sensor or the gas cap is always the reason the check engine light comes on is PURE SPECULATION and most often wrong.
Now don't get me wrong, I am not trying to discount the information, but when it is wrong, it is necessary to correct it.
But then again, who am I to say what information is wrong or right?
As I have stated hundreds of times and has been stated by several of my associates...........
A trouble code or the check engine light on does NOT mean replace the sensor. It means that there is a problem with the CIRCUIT.
Diagnose the problem BEFORE replacing ANY sensor.