Need help with miss on 99 k2500-5.7L
I have a 1999 OBS burb with 131K miles on it. I have a miss between 1500 - 2200 rpms. There is no code or SES light. I put it on a scanner and it does not show a miss. It is not in the trans, as I can get it to miss while in parkedl and rev up to 2500.
I have replaced the following:
coil (2 different brands)
seafoam in gas tank to clean injectors
and swapped from the old poppet valve spider to the ungraded injector spider
Still can't find miss.
Basically stock, has flowmaster cat-back, K&n filter, and a PCM4less computer. I have even put the stock computer back in. Same problem.
Motor still pulls strong to 5K rpm. If I am under light throttle and lite load, that is when the miss occurs. If I give it more gas, it goes away.