Starting issue

I have 99 grand am that has issues starting when warm. It will start but it its hard to get it started, now it has a bad idle almost wants to stall out. I have diagnostic done twice that shows nothing wrong with the car. Fuel pump turns on and reads that it hold pressure. I have replaced spark plus, boots, fuel filter, o2 sensor, used fuel injector cleaner & caberator cleaner. Still has same problems? I have seen 4 mechanics no one can diagnois the issue. Is there anyone out there that has had a grand am with the same issue? Anyone that has any idea what it can be? Cant keep wasting money and cant afford a new car right now. Please help.

Thanks

Tracy

One thought is cleaning the throttle body and IAC circuit. If air cannot get in, the car cannot run.

How come only when its warm though? When i first start the car and its cold it fires right up without hesitation and its cold in the morning, then usually most starts after that i have a problem.

When cold, the IAC opens up a lot to idle the engine up. Once warm, it doesn’t need to open as far, and dirt and crap cuts the airway even more.