Piero

I swap an l96 with 6l90e. I just tried to start it
but after 2 seconds it dies. Can someone help me, what to do to fix the problem.

jetech

ok 1st things 1st. Did you have VATS turned off in the ECM ?

Piero

When I bought the stand alone harness they said the vats was turn off from the ecm they send with it.
I swap the ecm to the one that came with the engine that I know havent been turm off the vats and dont even starts like with the other one.
I call a friend that have hp tuners and he check it, he said the vats is off.
He told me that the ecm was from an escalade, dont know if these is relevant.
I have some codes havent been avalable to solve.
P0641: sensor reference voltage "A" circuit/open
P2122: throttle/pedal position sensor/switch "D" circuit low input
P0107: manifold absolute/barometric pressure circuit low input
P2127: throttle/pedal position sensor/switch "E" circuit low input
I have changed the throttle body, the pedal, the injectors (they were bad)

the strange thing is if I put the original ecm only apears these code.
P2138: throttle/pedal position sensor/switch "D/E" correlation

jetech

Sounds like there is an issue with the harness power for the circuits you mentioned. Check to be sure you are supplying good voltage to the ecm on all wires that feed the ecm. Be sure you have good grounds for the ecm harness, battery to frame, to engine. Are you able to check fuel pressure with key "on" and while in "start" position ?