Reduced engine power

[aggie91]

OK, I am at a loss.

I have a 2006 Siverado 2500HD with the Duramax and Allison trans. My DIC displays "REDUCED ENGINE POWER". There are no DTC's at all, no check engine light. It drives fine as long as you don't floor it. Even in Neutral with my foot on the floor, it will only get to 2000 rpm's. I can go down the highway at about 75 max as that is about 1900 rpm.

I can't figure it out. I even disconnected both batteries over night and it did nothing. Starts up and goes right into the Reduced Engine Power mode.

I did some research, found a few that mentioned coolant issues. My is full and is not overheating. Trans temps are fine, oil pressure it fine too.

Its like the pedal/TB are not in sinc but this should throw a code in the PCM. There are not any codes. I've checked it with both a hand held scanner and my son's laptop with HP Tuners.

HELP!!!