well fellas its driving me and my mechanic mad. Heres the symptons, roll ons in any gear below "mid-range" (underload) it stutters until the car gets into the "performance range" of the power curve then she clears onto all 8 (so it feels). We have checked the tune and found several things wrong with it namely that everythings been turned off, all the sensors in the whole car basically. I'll not name the tuner but he is well known in Atlanta. Anyways the car was tuned in the winter months and we found that it was dangerously lean so we added fuel, then the plugs then the wires then the coil packs were replaced, checked the compression, checked the leak down, checked the injectors, checked MAF, checked the KPA, checked the timing, etc. etc. STILL found nada, still have the miss on the roll on and no codes even after everything was turned "ON"

Has anyone got any ideas? Im at the end of my rope, the local dealer is idiots and the ZO6 is in capable hands now but still to no avail. BTW my car is a 383 car with all the bolt-ons. To me it feel like fuel delivery and i originally thought it was bad gas but we blended 110 octane in her last night (about 10 gallons) and she still has not straightend up!

Please help or make some recommendations before i set this car on fire today.

Thanks in advance,
Shawn

 

WOW my blazer (00' s-10, lq9 engine, t76 turbo) recently picked up a VERY similar issue but from what i can tell after pullin the valve covers i have a slightly bent exhaust valve on cylinder one, thats sealing up when it heats up but under normal driving its leakin

 

 

So you can't determine the cylinder the miss is on?

 

I would be sure to check the plugs for cracks in the ceramic. Twice I have slightly cracked a plugs ceramic when torquing the plug down and it has cause the same symptoms; missing at low RPm and then it feels ok in the higher rpm's. It wasnt even throwing a code either. Just an idea for something to check. Have you even checked the plugs, wires, and the fuel supply system yet?

 

In my experience, a low rpm miss is most generally a plug or wire issue. If those were replaced then I would have to say you have a lean misfire condition or possible a mechanical problem.

A lean misfire makes more sense if it clears up with power enrichment. Just some ideas.

Dave