Have a 1991 305 Trans Am. It starts and runs great... After approx 15-20 mins. it starts to miss and the drivability becomes very poor. After shutting off, it will not restart. The car has only 9,000 miles on it. It's home is in a collection which is stored in a climate controlled garage. The fuel is brand new 93 octane. Fuel pressure is within specs, the spark is there... But no go. It will however fire up (roughly) with a spritz of starter fluid... It's as if once the ECM kicks in after warm up, it goes to hell. I forgot to add that this happens every time.. Runs great cold... Turns to hell when warm/hot.

 

Next time it doesn't start disconnect CTS (front of engine beneath throttle body) and then try. If it starts might first try changing the CTS sensor. If same problem persists after changing CTS you might then try checking injectors impedance. Should be around 16ohms.

 

Okay. I already tried disconnecting CTS.. Didn't work.. But I did do what you suggested and ohmed the injectors with a Fluke 333 meter. The readings ranged from 3.9 to 16.5. I'm under the impression that the injectors are shot.

 

Obviously 3.9 is bad. Good meter for sure. Replace all injectors, Multecs are notoriously bad. SouthBayInjectors on here has a good price on sets and an excellent service plan on their Bosch III injectors. I think if you mention thirdgen your get 10% off.