Hello, Ive been a lurker for a while. Ive got a 91 Z28 5.7l tpi


I have gotten the check engine light twice recently, but by the time i shut down the car and use my super special paper clip to read the codes, the light goes away.

It seems to happen when I drive after having sit in traffic and the temp raised a bit.

Any Ideas?

 

Codes are stored in the ECM. Turn off the car, put the paperclip in, and turn the key to on (not start). Read codes.

 

Yeah, I know


Thats what i did. It didnt give me any codes. I havent seen the check engine light sence yesterday. Thats why I posted.

I guess I am asking how can I check the codes when whatever the probelm was went away, and thus what triggered the check engine light?

 

once the light goes on the code should remain in the ECM's memory until it's cleared, even if it's an intermitent problem.

 

If the ecm isn't storing the code the ECM is bad, or it somehow lost it's constant feed of power. Since it's fused with the fuel pump, this could only be a wiring issue.