OK heres the problem, iv posted before about this issue but ive come accross new information that might help my cause.

My 1997 4.2L V6 (manual Trans) has had a missing issue for a few months now, first plugs and wires were replaced (all OEM), that fixed some of it than it came back and got progesslevy worse. turns out the cam sensor had gone bad so I had that replaced. it still has a small miss/stumble under acceleration and only under acceleration it runs nice and smooth while crusing or deccelerating.

While we had the computer hooked up to the truck before the cam sensor replacement we noticed both banks were running a little lean and the spark advance was jumping all over the place at idel. when I would push the accel peddle the spark advance would jump a little than bottom out at zero and stay there untill it returned to idel (we only did short bursts, we never held a high RPM to see what would happen).

I havent had the computer back on it sence than but was wondering if the knock sensor would also be a possible culprit.

Thanks for your help.

 

Your running lean for some reason, probably have some spark knock. Probably an O2 sensor or Mass Air Flow Sensor as they have an effect on how rich or lean your engine runs and will cause your hesitation. The MIL should be on if there is an issue but mine showed similar symptoms long before the computer finally let me know they were faulty........... Good luck