Was running great then sounded like it wasn’t running quite rite. Then developed a backfire at idle. A quite large one Off idle no backfire but can hear something that resembles a ping/detonation and a very slight engine stubble. I have been advised via phone call to BUP that possible injector plugging from paint. But curious if anyone else has ran into this issue before I yard my fuel system apart.

gonna try to get it scanned to verify it is fuel related

new plugs/ wires. Moved coil packs around. Same cylinder backfireS in all configurations Isolated via pulling plug wire

Either fuel system or possibly a pushrod has pushed through the rocker arm so valve isn't opening. There have been a few that have done it. Mine included. More likely the fuel system since it's a known problem.

Only backfires through exhaust never the intake