90 gmc k1500 5.7 tbi backfire problems

[Darkelden]

Thank you all for you help. In the end i did figure out what was wrong.... it was me. When i was setting timing on the engine i was unplugging the wrong device for timing. On my truck there is two identical one wire connectors right next to each other on the back of the motor. one was a extension for the O2 sensor and the other was for timing. as you can guess this whole time i was unplugging the O2 sensor then trying to set timing. Once i was able to actually set timing at zero, i was able to adjust my base idle and correct the TPS.

 

[Trlrider]

"... it was me. When i was setting timing on the engine i was unplugging the wrong device for timing."

LOL, late to the thread so I read thru the whole thing to see if anyone had suggested this before commenting.

Good your figured it out before you screwed your fuel tables all up.