I just bought my 88 gta about 2 months ago. The check engine light comes on about 50% of the time on start up, and will stay on until i start it again which it wont happen or it will. The light is for the mass airflow sensor, but i know that my maf was replaced but not 5 months ago, and my mechanic checked it and said there is nothing wrong with it. So what happens is when the check engine light comes on it idles funny, usually lower, and not as consistant. Can anybody please tell me whats going on?

 

Your car is trying to tell you something is wrong. The check engine light comes on when a problem exists...i.e the rough idle... and should throw a hard code. You need to pull the code with a scan tool to see what is going on.