"Service Engine Soon" light - '95 1500

[mirvin]

The light keeps coming on. It turns off after a couple miles, then comes on again.
Anyone know of a good shop in the South Bay or Long Beach to get it checked?
Pep Boys wants $85 just to hook up to the computer and Chevrolet says I gotta leave it for at least a day!!

[al cole'holic]

mirvin:
The light keeps coming on. It turns off after a couple miles, then comes on again.
Anyone know of a good shop in the South Bay or Long Beach to get it checked?
Pep Boys wants $85 just to hook up to the computer and Chevrolet says I gotta leave it for at least a day!! Do you have an exhaust system or headers on it?

[mirvin]

Yeah, there's a flowmaster exhaust, not sure if it's a CatBack or just a muffler and tip. No headers. BTW: 98,000 miles.

[al cole'holic]

mirvin:
Yeah, there's a flowmaster exhaust, not sure if it's a CatBack or just a muffler and tip. No headers. BTW: 98,000 miles. I would say have a "hole-in-the-wall" muffler shop take a look at the exhaust, check for leaks etc...if you take it to Chevy they will most likely tell you its the exhaust system. That idiot light for the early 90's pickups was for exhaust sensors mostly...good luck :D

[mirvin]

al cole'holic,
Thanks for the info. I figured it was the oxygen sensor or one of the many other sensors, maybe the cat converter.
I've been driving it like this for months and just figured I should have it looked at.
Thanks again.

[al cole'holic]

mirvin:
al cole'holic,
Thanks for the info. I figured it was the oxygen sensor or one of the many other sensors, maybe the cat converter.
I've been driving it like this for months and just figured I should have it looked at.
Thanks again. No problem :D I have put so many sets of headers on the 92-95 year trucks that I had, I remember puting black tape over the service light and just leaving it alone...

[fixit1002]

I dont want to say that was bad advice but im sorry its not an idiot light it is most important and if you keep driving you can cause some big prob i have been a mechanic over 20 years and a smog tech for over 12 if it sets a lean code it means fuel pres or vac leak or possable senser no matter if its a fuel prob i sure wouldnt want to take my fam acrosss the desert pullin a boat with a prob like that anyway jump the aldl connector if its a 95 its still obd 1 jump the connector at the far right count the flash and post the code ill tell you what possable problems it could be sorry for soundin however cant help it i take that light seriosly
fixit

[Dr. Eagle]

I agree. You may have a problem with a sensor, or a lean condition can be caused by something as simple as a dirty fuel filter. The big canister filter on the frame rail on the drivers side. If you have not changed it in a while might be a cheap place to start. Next have you ever changed the oxygen sensor? If no, then another worthwhile investment. Bottom line, you don't want to keep driving if it is running lean as you are likely going to destroy the valves.
In any event it is best to figure out what the computer is trying to tell you. It is definitely putting out some kind of fault code. That means that something is happening that is outside of the normal operating parameters, or is beyond the computers ability to compensate.
BTW I had a 1992 1500 suburban with a 350 and I now have a 2500 suburban with the 496, put cat back flowmasters and K&Ns on each of them and never had the check engine light come on. pig_flyi In any event with the light coming on... Don't ignore it!
[ September 25, 2003, 09:46 PM: Message edited by: Dr. Eagle ]

[mirvin]

So I finally got around to jumping that connector and got codes 12 and 32. Talked to an emission style mechanic friend (Smog Pros) and he said it was probly the MAP sensor or the O2 sensor> he said not to worry about it and bring it back when I can leave it all day. I told him I was gonna pull my boat with it and he said no problem.
Pulled the boat to Buena Vista and back and the "Service" light didn't come on at all the whole trip!!
Dr. Eagle: Thanks for the tip. I'm gonna start with the feul filter and go from there. Truck just turned 99,000 miles so I might as well start going through it.....

[TrojanDan]

Replaced my Map Sensor about 14 months ago on my '94 C1500 5.7 after the Service Engine Light kept going on. Runs great for the 12 miles to the launch ramp and back. :cool:

[Dr. Eagle]

Yeah, I think it was like 55000 miles when I first did the fuel filter in my 1992 K1500 Suburban. You are supposed to do them every 15K.
If you haven't done it by now I bet your little fuel pump has been working overtime trying to get fuel to the motor. That may clear your problem up alone. But if you have that many miles on it a new Oxygen sensor is not a bad idea either.
[ October 01, 2003, 06:14 PM: Message edited by: Dr. Eagle ]

[Rexone]

Problem is when you don't change the fuel filter and it gets plugged up it overworks and ruins the fuel pump to the point it pulls too many amps and won't perform even with a new filter. Experienced this with a used 96 sub I bought. Had to drop the tank and change the pump :( Then all was good again. (change the filter, often). :)

[24sleekenforcer]

Mirvin ,the code 12 is a normal system check, now the code 32 is EGR problem. I would check vac hoses to the valve and solenoid.Also maybe a bad solenoid. I have also seen the port between the valve and the TBI plugged also.If you don't have a cat conveter not much you can do, not enough back pressure to operate EGR.Just some things I seen.

[mirvin]

Ok, just ordered a map sensor, egr, 02 sensor and a fuel filter. I'll letcha know what happens.
Thanks guys.

[mirvin]

So this morning I changed the feul filter and the EGR Solenoid. No dice. Looks like it's on to the EGR Valve and map sensor.

[Dr. Eagle]

Ok after you were done, did you reset the computer? Before giving up on the work you did and moving on, disconnect the negative battery cable and let it sit for about 10 minutes. Reconnect the cable and then start the motor and see if you still get the service engine soon light.
The computer keeps the fault code in memory for some time.
[ October 03, 2003, 10:15 AM: Message edited by: Dr. Eagle ]

[mirvin]

Ok after you were done, did you reset the computer? Thanks Doc!! I was not aware of that. I'll do it before my evening commute..
Everyone here gets five from Mirvin!!! :cool:

[mirvin]

So I reset the computer and yep, the light came on again. Went ahead and changed out the MAP sensor and EGR valve and blammo, no light as of yet!! Drove it all weekend and into the office this morning. Also had a noticable performance boost (recovery) after changing all these valves and sensors!!
I still have the O2 sensor. Change it or return it?? :rolleyes: :cool:

[24sleekenforcer]

Well I would return it only becuse you did not have an O2 sensor code.(13)good luck.

[Dr. Eagle]

Personally I would just replace it. Even without the code with the mileage you have on the truck it is just a matter of time before it does quit working.

[HOSS]

Now remember to clear the codes.

[HOSS]

Now remember to clear the codes.

[GofastRacer]

Wow, sure glad I don't have to deal with all those issues, my truck just runs and runs and runs and runs!!.. :D :D :D

[Dr. Eagle]

GofastRacer:
Wow, sure glad I don't have to deal with all those issues, my truck just runs and runs and runs and runs!!.. :D :D :D Or at least you think it does.........