ctgreddy

car is a 02 v6 body with full '01 gt drivetrain that we just put in. car was running great the past 400 miles. but now when at part throttle(about half) it leans way out and pegs his wideband, so past 18:1, and jerks some, kind of like it's missing. He's still got his v6 fuel pump so I was thinking maybe that was just not supplying enough fuel, but it just started doing it recently. has new fuel filter, plugs, and air filter. it's a full bolt on car with a mail order tune, so I was also thinking maybe the tune is bad or something, but there again, it just started doing it recently. Any ideas?

cliffyk

I assume you are using the '01 PCM? If so then disconnect the battery for 5-7 minutes to reset the KAM and see if things change--it may be that the adaptive learning has learned badly.

Can you run any data logs to see what the fuel trims and other parameters are doing?

ctgreddy

yeah the pcm was the same as the motor/wiring. but we figured it out. ended up being a bad coil pack on cyl 1. i thought it was going to be a fuel issue, but got a code for cyl 1 misfire, checked the electrical on both the coil and fuel inj, then swapped coil packs to another cylinder and it switched cylinders so got a new one and is good as new.