96 Chevy 5.0 4x4. random multiple misfire

Question

I have changed crank sensor plugs wires coil distributer. Gear on bottom of dist. Set can retard with computer.   If u floor it  it sounds like it's running good on all 8. At a cruise it gets worse.   Starts popping out exhaust.   Low rpm runs like shit.  Changed egr also.  Checked for vacuum leaks.  Don't know what is next.

Answer 1

Inside the distributor the cam position sensor tends to shift out of position, this is common, even if you replaced the distributor with new and index it, you would need to make a new position with the distributor hold down clamp to properly be index,