"service engine soon" light on 2002 Trailblazer [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: "service engine soon" light on 2002 Trailblazer


texas arsenal
05-10-2005, 04:44 PM
I have a 2002 Trailblzer LS and have absolutely loved since I drove it off the dealership lot in Oct of 2001. It has just under 58K miles on it, its garage kept and is completely babied. At about 57k miles the service engine soon light came on. I checked the gas cap (and would later replace it) and everything looked fine. The car runs great but the light wont go away. I used a Davis Instruments CarChip in the OBDII port to see what the error code is and to check the overall performance. It turns out there is a misfire in the number 2 cylinder on start up and only on start up. Other than that no problems what so ever.

My trusty mechanic finds the same thing with his diagnostic equipment and suggests I replace the plugs and the number 2 ignition coil. I know the plugs dont need replacing at only 57k but I figure I will try it. That does not fix the problem.

I love this car but the "service engine soon" light is going to push me to trade it in for a Nissan Pathfinder.

Anyone have any ideas, thoughts, comments???

02EnvoySLE Guy
05-10-2005, 05:41 PM
Well my thought is don't trade for a Nissan, trade for another TB!!

Beyond that, I really don't know what to tell you. You said you DID replace the coil on that cylinder as well as the plug? I'd start there.

Also you don't happen to have an aftermarket alarm system, do you?

Info - Misfire DTCs P0300, P1380, P1381 and Catalytic Converter Damage Due to Installation of Alarm Systems #02-06-05-004A - (Jan 9, 2004)
Misfire DTCs P0300, P1380, P1381 and Catalytic Converter Damage Due to Installation of Alarm Systems
2004 and Prior GM Passenger Cars and Light Duty Trucks

2003-2004 HUMMER H2

2004 and Prior Isuzu Light Duty Trucks

This bulletin is being revised to add the 2004 model year and include specific DTCs in the title line. Please discard Corporate Bulletin Number 02-06-05-004 (Section 06 - Engine/Propulsion System).

General Motors Engineering, in an effort to determine the root cause of catalytic converter damage, has determined that aftermarket alarm systems incorrectly installed in vehicles have the potential to cause misfire codes and damage to the converter. These alarm systems use a circuit interrupt which utilizes the ignition circuit on the vehicles.

These alarm systems utilize mechanical relays and normal vehicle movement can trigger these relays to engage and disengage the ignition circuit while the vehicle is in motion. These disruptions of the ignition circuit, which occur in milliseconds, may cause more fuel to be commanded. Over time, this dumping of fuel on and off again can cause misfire codes and ultimately damage the converter assembly.



Important

Engineering could not identify any alarms that utilize solid state circuitry that would eliminate this concern. Because of this, it has been determined that all alarm systems must be routed through the starter circuit in order to avoid this condition.



Dealers must be aware of this issue and take note of the wiring on vehicles with alarm systems that come in for repair, particularly for catalytic converter damage that seem to have no known root cause.

I also found this:

Engine Misfire due to Injector Fretting Corrosion - kw 2.2 3.1 3.4 3.8 4.2 4.3 4.8 5.3 6.0 8.1 adaptor chuggle fuel hard idle lamp light L36 L1 L18 L61 LA1 LG8 LL8 LU3 LR4 LM7 LQ9 LQ4 LN2 MIL misfire #PI01353A - (Dec 19, 2003)
Engine Misfire due to Injector Fretting Corrosion
.

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=1416911&psdid=199&evc=sm#ss1-1416911">Condition/Concern:

This is a supplement to bulletin 03-06-04-030 for driveability symptoms of long or hard starts, chuggle, rough idle and light or intermittent misfire. The malfunction indicator lamp (MIL) may also illuminate.

<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=1416911&psdid=199&evc=sm#ss2-1416911">Recommendation/Instructions:

Analysis of returned Multec II injectors indicate that terminal fretting corrosion may also be responsible for the conditions described in this bulletin. Fretting corrosion (microscopic in nature) is nearly impossible to detect in the field. Symptoms of fretting corrosion may be a miss that is corrected after the injectors have been disconnected and then reconnected cleaning the terminals in the process. The most effective method to correct this condtion per field comments is to remove the connector and apply/inject dielectric grease, P/N 12377900 (in Canada, P/N 10953529) to the female terminal. Be sure to cover both cavities and reconnect the injector. Please refer to bulletin 03-06-04-030 and/or June 2003 TechLink for further information.

.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=1416911&psdid=199&evc=sm#ss3-1416911">Models:

(00, 01, 02, 03 Buick Century, LeSabre, Park Avenue, Regal) and (02, 03 Buick Rendezvous) and (02, 03 Cadillac Escalade, Escalade EXT) and (03 Cadillac Escalade ESV) and (00 Chevrolet S-10) and (00, 01, 02 Chevrolet Camaro, Lumina) and (00, 01, 02, 03, 04 Chevrolet Cavalier, Impala, Malibu, Monte Carlo, Silverado, Suburban, Tahoe, Venture) and (01, 02, 03, 04 Chevrolet Express) and (02, 03, 04 Chevrolet Astro, Avalanche, Trailblazer) and (03 Chevrolet Blazer, S-10, Trailblazer EXT) and (00 GMC Sonoma) and (00, 01, 02, 03, 04 GMC Sierra, Yukon, Yukon XL) and (01, 02, 03, 04 GMC Denali, Denali XL, Savana) and ( 02, 03, 04 GMC Envoy, Safari) and ( 03, 04 GMC Envoy XL, Jimmy, Sonoma) and ( 00, 01, 02, 03, 04 Oldsmobile Alero, Silhouette) and (02, 03, 04 Oldsmobile Bravada) and (00, 01 Pontiac Transport) and (00, 01, 02 Pontiac Firebird) and (00, 01, 02, 03, 04 Pontiac Bonneville, Grand Am, Grand Prix, Sunfire) and (01, 02, 03, 04 Pontiac Aztek) and (02, 03, 04 Pontiac Montana) and (03, 04 HUMMER H2) with 2.2L, 3.1L, 3.4L, 3.8L, 4.2L, 4.3L, 4.8L, 5.3L, 6.0L, or 8.1L Engine (VINs F, 4, J, E, K, S, X,V, T, N, U, G - RPOs L61, LN2, LG8, LA1, L36, LL8, LU3, LR4, LM7, LQ9, LQ4, L18) and Multec II Fuel Injectors)

Only other question I would have is if the engine is using the oil or coolant at all, or if there are any other strange noises from the valvetrain at idle. Seems like those are the only other things connected to that condition.

Did your mechanic use autotap to monitor the engine as you went down the road with it? Might want to do that, just to be absolutely sure the misfire only happens at startup. Did the misfire happen only once, or until it warmed up?

texas arsenal
05-11-2005, 08:49 AM
Thank you for the great info. This would support what the dealer told me.

I used a Davis Instruments CarChip in the OBDII port and it time stamps the misfires and error code and it was always at start up.

I guess I can have the dealership replace the valves but that will be an expensive "this might fix it".

texas arsenal
05-11-2005, 08:49 AM
BTW- there is nothing aftermarket (except replacement tires) on this vehicle.

02EnvoySLE Guy
05-11-2005, 11:21 AM
Thank you for the great info. This would support what the dealer told me.

I used a Davis Instruments CarChip in the OBDII port and it time stamps the misfires and error code and it was always at start up.

I guess I can have the dealership replace the valves but that will be an expensive "this might fix it".

I look at it this way: If you go in with the complaint of misfires at startup, and open an RO, the dealer will replace whatever they see fit to replace to fix the problem. If the problem isn't fixed the first time, THEY pay for subsequent replacement parts since their original solution didn't fix the problem. And if you're under warranty (original or extended GMPP) the deductible should cover it.

FYI all of that info came directly from GM via the factory service software, same as the dealership has access to. :D

04TBEXT
05-11-2005, 01:41 PM
Based on what you're saying, I would question fuel quality and its' possible relation to injector contamination. Since fuel atomization and mixture is absolutely paramount at cold start-up, this is the first place I would investigate. Has any one performed an injector drop test..attempted cleaning the fuel injectors??? I might suggest taking a step-by-step approach... Since this is an intermittent (cold start only) condition, I might try some baseline things, before "throwing parts at it". No disrespect, but changing out parts can become a expensive and frustrating proposition. I have encountered this concern multiple times on my Suburban. Each time injector contamination was the cause. My first step approach was by adding GM Fuel System Treatment P.N. #12345104. This treatment with 20 gallons of fuel resolved by issues on both occasions, completely. I now have 67K on my vehicle; "clean" start-ups, smooth idle and acceleration and no "SES". If you should choose this path, use no other...repeat use no other than the GM treatment. I have tried other which did not remove the contaminants ... I almost bought & installed an injector I didn't need. I can't say this is a direct repair to your concern, but our symptoms were the same. If you should choose to use a dealership...be cool. Remember, they're working with an intermittent condition on the day of repair which you may have been encountering on a day-by-day basis. They are not GODS, but regular people just like us. Pointing the finger really does nothing. After all, when the chain stores and independents can't figure it out...where does the vehicle end up???...at the dealership! Whatever path you should choose..good luck.

texas arsenal
05-11-2005, 03:20 PM
I am currently running a take of gas with an over the counter Valvoline injector cleaner. I will try the GM cleaner you mentioned in my next tank of gas.

Ive learned long ago you get more with honey than vinegar. I havent had any reason to be anything other that happy with the dealership I have been using. My only point of discontent came with my regular mechanic who suggested we replace the plugs and #2 coil. Which did not fix the prob.

02EnvoySLE Guy
05-11-2005, 05:13 PM
Keep rubbing it in.... :p LOL

Hey it's not like they're that expensive to get a set.... :m2:

texas arsenal
05-16-2005, 08:55 AM
Woo Hoo!!!! My SES light is finally off (fingers crossed) I used a 20oz bottle of the GM injector cleaner (pn 12345104 I think) that someone recommended and less than 50 miles into the tank the light went off.

Thanks everyone for the help and suggestions.

My baby is back!

texas arsenal
05-16-2005, 08:58 AM
BTW- That someone was "04TBEXT". Thanks a million, I owe you a beer.

texas arsenal
05-16-2005, 02:34 PM
@#!%$^**&^$@#%$%$%!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The SES light is back on


S.O.B.

coastie22
05-19-2005, 07:56 PM
I had the exact same problem and i have an '02 trailblazer LS. I took it in and 90 bucks later they just reset the computer and it was fixed. Sucks to pay for it, but without the proper tools you can't reset the computer yourself.

02EnvoySLE Guy
05-19-2005, 11:58 PM
I had the exact same problem and i have an '02 trailblazer LS. I took it in and 90 bucks later they just reset the computer and it was fixed. Sucks to pay for it, but without the proper tools you can't reset the computer yourself.

Actually, here's a fun tip for the future:

Every AutoZone has an Acutron-II OBD2 code reader which they will use for free to read your trouble codes. If you go in and real nicely ask, they'll hook up the machine and show you the button to press to reset the computer. Legally they can't do it themselves, but most will just let you do it if you ask.

Or you could always unplug the negative battery lead for a few hours and let everything clear out on its own. :m2:

texas arsenal
05-20-2005, 10:47 AM
The light is back off again. Hopefully it will stay off as I have now burned a full tank of gas with the GM injector/valve cleaner.

I have a Davis Instruments CarChip which will display the error codes (via USB download) and allow me to reset the light.

texas arsenal
05-27-2005, 08:40 AM
The SES light is back on again and so is my search for a new vehicle.

Envoy Fan
05-27-2005, 09:25 AM
The SES light is back on again and so is my search for a new vehicle.

Sorry to hear of your engine problem. The '02's had some engine issues. Hope you will consider GM again, the Pathfinder is tempting, but they have problems also. :m2:

texas arsenal
05-27-2005, 10:37 AM
Sorry to hear of your engine problem. The '02's had some engine issues. Hope you will consider GM again, the Pathfinder is tempting, but they have problems also. :m2:

Im not certain that I will start car shopping. I am not very happy however with a car that has 58k miles, is well cared for and the engine light wont go off.

The only GM I would look at is a Tahoe.

Unfortunately the SUV's I would be most interested in are out of my price range. I love the Land Rover LR3.

deathbynosleep
05-27-2005, 02:33 PM
Im not certain that I will start car shopping. I am not very happy however with a car that has 58k miles, is well cared for and the engine light wont go off.

The only GM I would look at is a Tahoe.

Unfortunately the SUV's I would be most interested in are out of my price range. I love the Land Rover LR3.

My first choice was a tahoe. But i couldn't afford it. So i went with the trailblazer.