Working on a 2005 2x4 Tahoe that was at a shop for 2 years with no history, I know the ECM has been swapped, the throttle body has been replaced, the transmission and harness was also replaced with the same issues going on. The truck will start and idle and can rev the engine with no codes, as soon as you try to drive it goes into "reduced engine power", throws a few codes I will list below, the stabilitrac and traction control come on as well. The vin doesn't match the ECM, the build date on the Tahoe is 09/05 and the vin is 1GNEC13Z46R145163. The ECM has a vin of 1GNEK13T83R120907 and an OS of 12579405. I have disabled VATS with no change. Do I need to rewrite the tune from a newer Tahoe file and if so which OS? Not really worried about the vin matching but would like to drive the vehicle again.
P1518- electronic throttle body to PCM communication
P0740- torque converter clutch solenoid circuit
P0753- shift solenoid A
P0758- shift solenoid B circuit
P0785- shift/timing solenoid
P1638- generator F-Terminal circuit
P1860- TCC PWM solenoid circuit
There was another generator terminal circuit that was in the history but I cleared the codes before I wrote them down.
-UPDATE-
I was able to drive the vehicle slowly down the road, as soon as it gets above 20% throttle it goes to reduced engine power, the transmission shifts to at least 3rd gear, repeats the list of codes again, i can clear the codes and drove it back home.