I have a 2008 Vortec Max with a 6.0L that has been convertered to run off
of Compressed Natural Gas as well as gasoline. It is driver controlable to pick
what fuel to run off of. When running on CNG it is setting P069E in the Ecm and P2635 in the Fuel pump control module. I took care of the P069E in the Ecm with Efi, but the P2635 is still commanding the MIL through the FPCM.
Any ideas?

Thanks