My 91 camaro fires up runs for a few seconds but then it dies out. I can't figure out what's wrong... it gets gas. I changes the IAC valve but that didn't fix it. Please give me some ideas.

 

It might be getting gas initially, but the pump could be going bad and can't keep up with demand. Or the filter could be badly clogged.
Could be a bad ignition switch, but then it should kill as soon as you back off with the key. To test that, don't let off the key once the engine starts (no, you won't hurt the starter). "Start" and "run" are two different contact positions on the ignition switch. If the engine still kills, you know it's not that.
Is your engine a V6 or V8?

 

its a 5.0L V8

 

Ignition control module maby or could be your timing is off. Can you make the car keep running by feathering the throttle?

 

Thanks for sharing information.