I bought a 91 3.1l v6 Firebird and I’m trying to bring it back to life. The car cranks and will turn over for a second on starting fluid.I ended up replacing the entire fuel system but the injectors just won’t pulse. The injectors are receiving power but they aren’t getting the pulse signal. I replaced the ICM already and I think it might be a sensor or the ECM(hopefully not). But I’m not sure what sensor or how to check them. I’m sorta new to cars, so I was hoping someone on here could help me. What do I do?

 

Scan tool makes checking things really easy but you can do without one. Start by checking for check engine light codes by jumping A and B on the ALDL connector. It may point to the TPS as a TPS that reads >2.5v will prevent the injectors from pulsing.
https://www.thirdgen.org/forums/v6/1...-sensor-2.html

 

Does your fuel pump do the 2 second prime when the ignition key is turned from off to run ? If no, a quick check of this fuse should be your next step here......

 

Thank you for the help. I tried jumping the A - B on the ALDL connector and my engine light never came on when I turned the key to the on position. Should I check and see fit he bulb is burned out? (Every other light on dash still works) If so do you have any links to help me take out the gauge cluster? Also the TPS is working but the IAC isn't receiving any power, I followed the wires all the way to the ECM inside the car and there were no kinks or accidentally grounded wires so I assume it's an ECM problem or PROM problem. What should i do?

 

I don't have my factory service manual handy to post the exact procedure, but the next check would be to make sure the distributor reference pulses are making it to the ECM . I know you said you replaced the ICM and that it fires up for a sec on starting fluid, perhaps the wiring from the ICM to the ECM is defective. This would leave it still able to make sparks, but with no injector pulse.

As to jumping the ALDL, you did jump the top two righthand terminals, yes?

 

Sorry for all the dumb questions this is only my second car but how could i check that wire from the ICM to the ECM? As for the ALDL, I did Jump the top righthand A and B just and i tried 3 paperclips and a wire but still no response from the car.

 

I don't want to sound as if I'm putting you off, because I'm not, , , , but, at this point it'd be for the best for you to get a copy of the 1991 Factory Service Manual for your car, it has all of the procedures for all of the tests that will pinpoint the problem. Like I said, at the moment I don't have access to my FSM (still in storage from a recent move) so I have no idea of the wire colors or terminal numbers you'd need to check to see if the distributor pulses are in fact making it to the ECM. I know a paper copy of the FSM is expensive, if you can find a digital copy it'll be cheaper, but either way if you have plans of keeping this car it'll absolutely be money well spent