[BabyDiesel]

Thanks so much! That's a crazy amount of info. Do you still have pictures of those wiring diagrams?

I never got them from Koots, unfortunately

Also, check both the C-code and J-code motors for cracking. They both came from GM, same manufacturing, same materials, just different applications.

I actually haven't even seen any 6.2 or 6.5 with EGR. On a sidenote, EGR is also often quoted as a trouble source when running on veggie oils.

The C-code were EGRed with the pumper sitting right in the intake part of the intake manifold. Most 6.2s found in 1/2 to 1 ton vehicles were EGRed. Some non-emission variants and the military motors had the EGR factory deleted with a clean intake manifold. J and C were letters in the VIN numbers.