89 Grand Prix won't start

[mfisys]

My son has a 1989 Grand Prix with 3.1 engine. He recently crashed it into a bank on our 3/4 mile lane. Since the crash, it will not start or even fire.

Damage seems to be limited to the right front fender, right headlight, parking light, turn signal, bumper & some damage to hood on right corner.

We have fuel pressure at the schrader valve on the fuel log, at least while jumping the fuel test wire to 12 volts.

Engine will start on ether then stops.

The Service Engine Soon light never comes on at all.

I checked all the fuses & didn't find any blown.

I figure since the Service Engine Soon never comes on, the ECM isn't triggering the injectors.

Is there a reset that must be done after a crash similar to what some Fords have for their fuel pump circuit?

Is it normal for the Service Engine Soon light to not come on after a crash?

Thanks for any help

John

[spinktec]

I don't know of any fuel system cuttout like on Fords. Since it runs on either, I would agree with your pursuit of the fuel system. You said It had fuel pressure at the rail (schrader valve) when you jumpered 12V , but is the fuel pump cycling on for a few seconds when the key is turned to ON? If it doesn't, then that's the problem and I would look at the underhood relay center at the "front right" of the engine compartment. I believe the fuel pump relay is in there. I know that doesn't account for it not running while the fuel pump is jumpered, but I'd still poke around in that box for a while to see if any wiring is fouled, because either way at this point it becomes an electrical problem. I can't imagine all the injectors breaking at once one or two maybe, but the engine would still run, albiet crappy. That leads me to where you are, the ECM. Did some wiring in the relay box get shorted during the crash killing the ECM alltogether? Check to see if the Service engine soon flashs a code (12 I think) when the diag port under the dash is is shorted (pins 1 & 2 I think). If there's no life, then the ECM is dead. If your asking yourself would it still spark with a dead ECM the answer is: I'm pretty sure it would, because the crank position sensor is wired directly to the ignition control module/coils, so as long as there's voltage it'll spark...I speculate. That's it, I can't think of anything else.

[mfisys]

Thanks for your reply.

We got it figured out this afternoon. When checking for power to the ECM on the wires where it should come in according to the Haynes manual, we found no power on the orange wires that supposedly coming direct from the main power distribution. After tracing them across the front and back the left side of the engine compartment to the fuel pump relay and fuse, I found that the fuel pump fuse was blown. My son had supposedly checked it but apparently didn't see that it was blown.

Apparently the power doesn't flow exactly as the Haynes manual says.
I couldn't find a 20 amp fuse that supplied the orange wire to the ECM directly (hot al the time) but the 20 amp fuse that feeds the fuel pump relay from the ignition switch also feeds the ECM's orange wire.

Anyway, after I replaced the fuse, it starts and runs fine.

Thanks again for your help

John