ok this is a 94 lt-1 trans-am. Car runs fine as long as you dont slam the gas....but once you do and you reach around 4000rpms the car sputters terribly and wont even shift into the next gear. We have replaced the cap and rotor,new plugs and wires,and had the car put on a diagnostic computer and it said mass air meter so we tried replacing that also but nothing works. Any ideas would help alot. Thanks Joey

 

Your catalytic converter(s) clogged by any chance?

 

cats are gutted

 

fuel filter?

 

I thought about the fuel filter but would it make it sputter at just high rpms? It very well might be it, I dont think its ever been changed on the car. Thanks for your help