barndog77

Alright...my car runs fine until 3300-3500 rpm or so...under normal excelleration or hard, it doesn't matter...it acts like it goes down a cylinder. It then idles terribly and sputters/pops if you hold it around 2500 or whatever..then hiccups, and goes back to running just fine. WHAT THE HELL??? Items replaced so far: Fuel filter, fuel pump (had low fuel pressure when we tested it, back to normal now..we thought that was the original culprit) air filter, ran some injector cleaner through it, and new front O2 sensors. The SES light randomly comes on and goes off on it's own, and the PCM shows no code history. According to the fancy scanner at my friend's shop, everything is fine and dandy. The motor has a bigger cam, a little head work supposedly, the pcm was tuned by speed inc. after i bought the car, all the free mods yada yada yada...no problems 'till recently...hell it went 12.65 @ 114mph on street tires! SO yeah...a little help here?