Really? You replaced the fuel filter already? Have you checked your Catalytic conver to see if it's clogged?

 

yeah i replace it when i got the car and did a full tune up on it to and there is no Catalytic conver. the people tha own it before we did took them off and put straight pipe on all the way to the back and put a ricer tip on it

 

Maybe that's your problem then! (No back pressure) Is there any muffler on it at all? I can't believe you've done a full tune up AND pulled the codes and still nothin'!! That's crazy! I wish I could see it in person, maybe I could help more.

Is it always between the EXACT same rpm range? Walk me through exactly what happens, from start to finish.