Ok i got this 97 camaro 3.8L and it runs really rough (no acceleration or power). I've replaced the catalytic converter, spark plugs, wires, and the ignition coil and still have problems. I would like to know if somebody has gone through the same problem and what was wrong with the car. I really would like to fix it.

Chugging when giving it gas. i've had the plugs/plugwires, pcv valve, fuel filter, emissions canister, fuel injectors cleaned and nothing has fixed the problem...... the only thing left is the oxygen sensors and i have four of them and it will run me another 500 dollars just to repair that. i've already spent 550. on the repairs above. the car is a piece of junk or the repair shops i've been dealing with can't figure out what's causing the "evap system' error code to come up on my computer.