my problem started after i sealed my intake manifold leak ,sorry my car is an 1995 trans am auto stock except for cold air high flow cat and exhoust started it up sounded fine took it for a drive hesitates sounds horrible no backfires shakes at low rpm acceleration.I rechecked every inch of my work no mistakes my car ran good before this.figuerd it might be opti took it apart to inspect looked very clean it is only 2 years old tested wiring to coil pcm every thing checked out.Ialso checked fuel pressure 36 at idle and 43 with vac off. I did notice with vac on when i give it throttle the pressure starts to go up then drops real fastto 35psi. I checked all my plugs and wires all checked out except the ones on the driverside appeard to be rich with soot and fuel smell.I decided to unplug my o2 senser and took a run in open loop it ran worst.I replaced my head gaskets two years ago thats what im starting to lean on going by the symptoms .as i said my opti looked good visually I have no programmer to moniter anything .thank you for any more Ideas.

 

I forgot to mention their are no thrown codes.

 

found half my problem had a bad fuel injector wire hanging by a strand. fixed that now i have high throttle miss sounds like machine gun when its wide open.

 

I would pull the pcm fuse and reset the computer and try again. Hope there is not damage to the injector wire.

 

I also found out myicm plug wasnt making a solid connection i just touched it and the engine stalled and set a 41 code.I squeezed the female ends of connector and the car runs perfect,i even cured my shaky oil presure needle.word to the wise always check your harness connectors before throwing money at parts this was the 6th pigtail problem i had since i owned this car 2 repaird 4 replaced every one gave me false opti,fuel trouble symtoms.