Service Engine soon

[OFusion04]

When it is real cold outside, and I start my 1990 grand am quad 4, the sevice engine soon light comes on. It also seems to turn the electric fan on aswell. When it warms up and then I shut the car off and start it again the light does not come on. What is the deal?

[Brad97GS]

Look at the link in my signature to read the codes. Then report back with the codes it gives you and we will try to help. :)

[OFusion04]

Can I test it even though there is no service engine soon light on?

[Brad97GS]

Yep. The ECM stores old codes. :)

[OFusion04]

checked the codes, it is showing a 26 code, thats all. So what does this mean?

[LargeFish]

I haven't dealt with that one, but if you have an auto. tranny I suggest you see if your TCC plug is making good contact. Search turns up:

http://www.gaownersclub.com/forum/showthread.php?threadid=33823

http://www.gaownersclub.com/forum/showthread.php?threadid=33290

http://www.gaownersclub.com/forum/showthread.php?threadid=32396

[OFusion04]

When I fire the car up, sometimes, not all the time it will smell like gas when it is cold out, also, I don't think the converter locks up when it is cold . I say this because the engine will rev higher until the trans is warmed up. so I imagine the converter will not lock up until a certain temp is reached. I have a bog off the line though, on easy acceleration sometimes.

[Brad97GS]

Correct, the converter is not supposed to lock up until the tranny gets warmer. So that's operating fine.

I'm thinking it has something to do with the engine fan. Code 26 is the Quad Driver circuit - meaning it's a part of the ECM that has four things connected to it. The engine fan, TCC solenoid, shift light (on a manual - takes the place of the TCC circuit), A/C clutch, and canister purge solenoid.

I would look at the engine fan or at the A/C system. Seems to be intermittent, so maybe you have a loose wire or relay for the fan...but that's a guess. My service manual has 3 pages of diagnostic flow charts...

[OFusion04]

Thanks for the reply. I do not use the AC as it needs a recharge. but it is real funny, because this service engine soon light only comes on when the engine is cold on start up, then the fan comes on. when the engine is warm and I shut it off then start it up again, all is fine.

[Brad97GS]

You don't happen to turn on the defroster when the car is cold, do you? The defroster uses the A/C so it can blow dry air onto the windshield.

Of course if your freon level is too low, the A/C compressor won't turn on anyway. I don't think that turns on the SES light though...

Hmmm...

[OFusion04]

yep I put the defrost on.

[Brad97GS]

See if the SES light goes on (and fan turns on) if you cold start it and leave the defroster off.

[OFusion04]

It is -21 today and the car was plugged in and I started it without the defrost on and the light came on and fan started up. I drove it for 2 minutes and stopped it. then started it and no code. so it is just cold I would think.

[Brad97GS]

Hmm...interesting. I don't know what to say except that you could have a slightly loose connection somewhere that is showing itself when cold. But that's a lot of speculation...

[eguyett1989]

I'm getting a code 62 on my 89 2.3LO GA...can you help me with the diagnostic tree on this code?