I have a 91 firebird with just the base 305 tbi. I got it less than a month ago (which is frustrating because i was presented a car described has having NO mechanical issues) and its bone stock, no modifications anywhere. It had been running fine, never any problems but lately when I started it the check engine light would come on but then go off after I drive for about 30 to 45 seconds. I didn't think it was a big deal and was gonna get it checked(until someone stole my wallet and now I'm broke). But today I drove it to school left it parked in the parking lot. No problems at all. Got back from school got in it and turned the key and nothing happened. It wouldn't even turn over. Nothing. I tried it a bunch off times, my first thought was the obvious that the barrier was dead but everything electric was working as it should and my gage was reading at about 12 Volts. I sat and thought what to do, then tried it again and it started with no hesitation. I took it home and shut off the motor and started it again, and it started right up. Any ideas? Thanks for taking the time to read this anything helps!
(I don't think it makes much difference but I should add it rained all day)

 

Do a search on VATS.

 

Ahh thanks that actually helped a lot. But why did it do that just that one time, was it just a glitch?

 

My '91 Formula does the same thing. Most times starts up no problems. Every once in a while it will do this. Take the key out, wait for three minutes, turn the key to run-not start-, wait for the security light to go out, then start. I tried to bypass it with the resistor by-pass but it still did it. Don't think the ECM is catching the resistor signal all the time. Good luck.

 

Thanks, so far so good. I took it to work and back and had no issues hopefully it stays that way.

 

It's funny, the first time mine did this it was raining all day. But it has done it on dry days as well.