92' 3.1L swap

[xLeGeNDx]

Heres the run down.

The body of my black car is shot but the engine and trans is the only thing that's in great shape on the vehicle. (92' GP)

I recently got a hold of another 92' GP with a blown 3.1L but has a good body and so the science project thus begins. The new GP has sat for an undetermined amount of time but everything appears sound.

I swapped the good 3.1/trans from the black car over to the green car, before the engine was pulled from the black car it ran smoothly, but now in its new home it wont even run it just cranks and cranks.

I pulled the fuel rail and sure enough all 6 injectors are not firing, so i started checking fuses, even swapped out the engine harness from the black car into the green one and still nothing. everything is properly grounded all fuses check out and everything.

Computer is operational.
fuel rail/lines are getting fuel
did the carb cleaner trick and got it to backfire.

What could i be missing?

[pocket-rocket]

How long was the good engine/trans sitting before it went into the new car? Any chance it sat long enough that the injectors are stuck shut? Will they open if you put 12 volts to them directly?

[xLeGeNDx]

the last time the good engine was cranked was maybe 3-4 weeks ago, and i haven't tried running 12 volts directly to the injectors

[xLeGeNDx]

So i Tried feeding the injectors 12 volts directly from the battery and they all shot

[SappySE107]

Are you getting spark? Maybe the crank position sensor is bad.

[xLeGeNDx]

I tried doing the carb cleaner trick down into the combustion chambers directly since i got the fuel rail off and i was able to get it to backfire but that was it.

[pocket-rocket]

Do you get code 13 from the computer? If so, something isn't connected between the ECM and the injectors, or your injector drivers could be shot. Have you tried swapping ECMs out?

[xLeGeNDx]

I was able to get the diagnostics code when i hooked up my jumper to the terminals, i've tried the ECM from the black car and the one from the green car and same results

[bszopi]

How about the fuses for the injectors? Or do the older cars not have them (I would think they do)? Also trace back all of your connectors to make sure everything is plugged in properly.

[pocket-rocket]

I don't recall fuses for the injectors on the W bodies. I just hope it's not something like a bad wire in the old harness that fried the drivers in both ECM's since I don't know what their tolerance to a dead short would be like.

[bszopi]

Here is a diagram for a 94 W-body (with a DOHC)...



As you can see, there is a fuse in the power wire before the injectors. If you have a multimeter, I would probe the wires for voltage. Since the ECM controls the injectors by completing the circuit by grounding it out, you should have a constant hot on one of the wires going to the injector. This will hopefully run out wiring issues from the power source to the injector, but not from the injector to the ECM.

[xLeGeNDx]

yeah there is a fuse for the injectors in the RS electrical center under the hood :P (which is good)

i've used 2 different engine harnesses and its still the same deal, using different ECMs that went to the harnesses then tried swapping that around as well

Edit: I tested to see if there was a voltage on either wire and none was present.

[pocket-rocket]

Well I'll be a monkeys uncle... No voltage huh? Then maybe that jump start terminal is cracked. I remember reading somewhere that someone was having all sorts of issues because their jump start terminal was bad. So in theory, if you fed the pink wire feed to the injectors some juice that puppy should fire right up. This shows you just how much I have to look at fuses over there. The only time I mess with underhood fuses is to pull the ECM fuse to crank the engine till I get pressure after an oil change to prevent dry starts...

[xLeGeNDx]

Jump start terminal? talking about the aux terminal by the battery?

[pocket-rocket]

Yes sir, that be the one. I use it for a jump start terminal at least... It's way easier to slap a cable on that then on the battery itself.