1991 Chevy 454 backfires, runs good, backfires, sometimes cycles

[pjksr1955]

Shortbus, Yes, I did change the entire distributor. I will check TDC this weekend. I changed dist. because truck was running bad. I thought it might be the ecm ? When I put new one in it ran the same.. thanks again, pjksr1955

Originally Posted by Shortbus

Did you replace the entire distributor? Just wondering since you can put them in 180 degree's off. Or even one gear tooth off and that can cause the problems you describe.

If you did you might double check by bringing number 1 cylinder up to TDC on the comp stroke and make sure the rotor is pointing to number one on the cap.