On cold start, the engine goes to high idle like it should, but has a misfire sound from the exhaust pipe. The engine also shakes a bit. When kicked down to curb idle, it idles rough and the engine shakes as if it isn't hitting on all six. When stopped at a red light in gear, the idle is very slow and rough. Idle speed in neutral is set to 750 RPM.
Sounds and looks like a burned exhaust valve because you hear it at the tail pipe and judging from the plugs looks like 1 and 6 are your culprits. Time for a compression and a leak down test.