LTFT bank1 & bank2 15% & 25% @ 2500-3000 rpm

TNTC5 · 07-29-2005, 12:09 AM

I have a problem even my tuner can't even figure out. The car have a skip @ around 2500-3000 rpm, but @ full throttle the car is fine. I hooked the tech2 and it show LTFT bank1 @ 15% part throttle & LTFT bank2 @ 25%. I will list all the things that i tried to fix before i take it to my tuner: new o2 sensors, IAT sensor, MAF sensor, new set of wires, spark plugs, flow the injectors, chek for burned wires, goto different gas stations. I did all that then take it to my tuner and he tried to put another tune in my pcm still didn't change. I also have p0174 code now and then poped up. If any of the corvette forum members come accross this problem please chime in. Thanks

Dixit · 07-29-2005, 02:05 AM

Can you reset the Fuel Trims on the Tech2 and see what it reads then? Or better yet, just disable LTFT and see the STFT fuel trims and see where they at.

Dixit

AVB · 07-29-2005, 02:07 PM

Check connections after the MAF which could be letting additional air in. Check PCV connections, manifold/egr leaks.

How does she run? Seeing any misfires?

TNTC5 · 07-30-2005, 12:45 AM

Thanks guys, she have alot of misfire @ part throttle, but @ wide open she run great. I have gone over and over again with vac. leaks. It there any methods of checking vac leak please help.Thanks ahead

ps. Just a few days ago i started to wash down my engine with water. I then started the car the idle raised up and sound like running on 7 cylinders and i couldn't get rid of it for a few days. You guys think that i have a vac. leak somewhere? I washed the engine after ttt.