no power to injectors
#16
04-21-2014, 06:02 PM
Power from the Ignition switch closes the power relay and also powers the Ignition system.
Pin 37 & 57 are the pins that power the computer up and they get their power from the NO contacts of the Power relay.
The computer grounds pin #58 & #59 to fire the injectors.
Fuse "U" is powered by the Ignition switch:
/
Pin 37 & 57 are the pins that power the computer up and they get their power from the NO contacts of the Power relay.
The computer grounds pin #58 & #59 to fire the injectors.
Fuse "U" is powered by the Ignition switch:
/
#17
04-22-2014, 07:56 AM
i tried my old 5.0 computer to test and see if it was the pcm and its the same way. the 5.0 computer was good before i swapped it out. i traced all the power and ground wires and nothing was broke or chaffed. all fuses and the diode are good. no burnt fusible links anywhere. its driving me nuts lol
#18
04-22-2014, 07:57 AM
I had as millibar problem where it would only start with brake cleaner and the. It would run perfect bit it was a bad PCM and the injectors would fire until it was started. I borrowed a friends PCM and it fried his computer where his truck had the same symptom. So it could possibly be a short somewhere in all those wires.
#19
04-26-2014, 05:22 PM
ok after alot of testing i figured out the ecm is toast. i think that 96 harness is what fried it. i put my 5.0 ecm back in it and can check codes and it will start up and run fine until it starts to lean out. guess its time to buy a new ecm lol. thanks for the help guys. this was so frustrating
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