I have a 91 Camaro RS with throttle body, manual. I have had the problem for at least a year now, but it's gotten so bad it can't be driven now. Has trouble idling/getting power- worse when it's cold. Car starts up fine, but will not idle by itself. I have to reve the car- funny thing is, it doesn't seem to get the power until I release the gas pedal. I can hold the gas pedal down, but it will just bog down and die. The jets from the injectors seem to spray just fine- nice even spray all the way around. Replaced the injectors, PVC, EGR, line to brake booster. I can't determine wheather it's a vaccume or fuel issue, but I'm leaning toward vaccume. My next step is to replace the Throttle body and intake gaskets, but wanted to see what you all thought before I go through that trouble. I read some posts that seemed similar that suggested changing the fuel pump, but my car isn't exhibiting the exact same symptoms. Thanks for your help!

 

Well sounds like maybe fuel pump BUT to cross that off the list have a friend come over. And dont' start just turn the key over to accel and then have you go under the car to hear the tank you should hear the motor running for like 3 seconds. Then have him turn it off for a few seconds and try again. do it about 5 times. if you hear any noise other than a continous buzzz. like sounds liek it buzzzes then goes low and garble and buzzes it will be your fuel pump.

 

Tried replacing the fuel filter? Sometimes dirt clogs the filter in a way that when there's more pressure (gas pedal down) the dirt clogs the hole, but without more pressure (foot off gas) the dirt settles allowing gas through. Anyway - fuel filter should get replaced yearly.