I can't get the Service Engine Soon light to quit. 1986 New L98 engine with less than 1500 miles on it. Keeps throwing a Code 33. Have also gotten a 34, 32 and 41 but it looks like that was all intermittent. Have read the FSM but don't have the resources to check the MAF like it says. I've heard that MAF's don't go out as much as people think and I'm not ready to condemn mine to the trash yet, especially for what they cost. I've disabled the EGR/MAF and the light still comes on. I've disconnected the battery and have re-set the ECM but the service engine soon light still comes on. But the car runs fine! Idles smooth @ 600 - 700 rpm, accelerates great, no hesitation. But the light is driving me nuts. Short of putting a piece of electrical tape over it to cover it up, would there be anything else I might try get get the light to quit? The light comes on within 15 to 20 seconds of starting and stays on all the time. Thanks for any advice.

 

It's pretty simple. Choose one course.

1. Fix it or have it fixed using the FSM procedures

2. Electrical tape.

 

You don't have a test light and a digital multi meter, or you do, but just don't know how they work ??

 

You might try replacing the relays. Those aren't expensive and
might be causing the many codes. Benny

 

Althought the 2 relays will only cost you $20, don't throw money at a problem. Find the problem and fix it

 

I don't have a test light and digital voltmeter AND unfortunately never learned how to use them. But you guys are right. Don't throw $$$ at the problem, just fix it. So I got my codes using an AutoXray EZscan 2000 and just to be sure, I went to the mechanic who put in the new L98 for me and re-scanned on his OTC 2000 Scan Tool. He kept picking up a code 15 which is a "Coolant Sensor / signal voltage high". It is also an "Idle Air Contol (IAC) sensor". We went by the FSM and after re-checking the connection, the scan showed the coolant sensor working properly. However, it was recently replaced and so was the IAC.

This is what I don't understand ... originally, the "service engine soon" light came on almost immediately upon starting the engine. After today, the service engine soon light now takes several minutes to come on. It's not intermittent. The light stays on until you turn the ignition off. I think maybe we made some progress. I disconnected the negative battery cable to clear everything. I'm thinking maybe as the ECM goes through the "re-learning process" the problem might take care of itself as the car runs fine and everything seems to be working properly. Wow, these cars are really tempermental!

What relays are you talking about? I'm all for replacing anything that might help. Also, I was told that most of my connectors for the coolant temp sensor, IAC, MAF etc. are pretty much brittle which could also contribute to the problem. I'm trying to find either the connectors with wire leads or even a wire harness. I've got so much into this thing now, a few hundred more wouldn't hurt. You can't take it with you!

 

Two times in the last 9 years, I got MAF codes. Both times I replaced the relays. Fixed. Fast, easy cheap.

 

A test light will run you $2.00 or so. An El-Chepo meter maybe $20.00. If you are planning on keeping the car those are not big investments.

Oh, the meter will come with instructions. I am not trying to be an azzhat here but if you are going to do the maintenance required on one of these odl buggies you must have the correct equipment.

 

You are so right. I'm changing the relays today just for grins. Then I'm off to get a probe and a meter.

 

I've got the shop manuals, but can you point me at these relays where I might get a visual of mine to check their condition? I'm planning to clean MAF soon, I've run K&N oil air cleaner forever and just replaced with a new one, from what I've read here it can be a culprit.

Car runs good, intermittent check engine but I checked codes, nada there. So just for mileage and hopefully a smoother running engine (not bad, but not perfect either) figured I'd do MAF cleaning and maybe replace the 2 O2 sensors behind the CATS as well.

thanks!

 

I cleaned my MAF sensor and a week later it died. Think long and hard before cleaning.

 

On the 86 I believe there are two relays, side-by-side, on the firewall near the battery. One is the fuel pump relay and the other is the MAF burn-of relay. Forgot which is which. It's been a while since I had an 86, so, guys, check me on that.

Also you can remove the MAF and visually check that neither of the very fine wires in the center is broken. When the MAF on my 86 died, I picked up one off a wrecked TransAm in a salvage yard. They're interchangable with Camaros, T/A, etc. Just compare the numbers on the underside. $50; ran fine for years.

Jake