The motor idles smooth.
Runs extremely rough under power, almost "skips" like the timing is going crazy. Strong weak, strong, weak, vvvvttt ,vt, vvtttt, vvvvvtttttt ....
Is pulling random misfire codes p300 and cylinders 3+4+6.

Compression in all cylinders is fine and holds.
The #4 plug was black, not tan like the other 5.
The #1,3+5 injectors measure fine.

If anyone can help point me in the right direction I would appreciate it.

 

Ummm. Cracked heads.

 

Got a picture of that plug to post?

What type of plugs are your running? I would start checking the middle plug wire, then the middle (#3) cylinder coil.

I'd also check your timing. I remember one member who only got a CEL when driving at high speeds, low to idle was fine. It turned out his crank bolt pulley was never tight, leading to a good bit of trouble in the bottom end.

 

I checked the crank pulley. Tight.
I replaced the plugs with new ones and it drives great now.
thanks.

 

Great! Check that #4 after some miles and see if it gets black again....there still may be something going on there.

 

just make sure you used oem plugs with dual ground straps