2002 Impala not starting
mrjb1923
01-22-2010, 08:25 AM
Hello All...
Need some help here...
2002 Impala cranks but does not start. We checked fuel pressure at the fuel rail and it registers a good 60 psi so that rules out the fuel pump. Used an injector tester light kit and it does not light (flash) during cranking. It does not show any codes via the OBD nor does it have a check engine light.
Replaced the Fuel Injection Module but no change.
Checked all fuses with a voltmeter to ensure voltage on both sides of the fuses.
Had the ECM replaced and reflashed, then it wouldn’t crank and pulled a P1631. Did the key relearn sequence and we are back to cranking but not starting and back to no codes on the OBD.
Radio was an aftermarket but still have the original, reinstalled the original radio back in and it says LOCKED (knew it would), and the security light is solid on with the key in the “ON” position.
Not sure where to go next as it’s driving us crazy. Help! Ideas?
Thanks...
Jerome
Need some help here...
2002 Impala cranks but does not start. We checked fuel pressure at the fuel rail and it registers a good 60 psi so that rules out the fuel pump. Used an injector tester light kit and it does not light (flash) during cranking. It does not show any codes via the OBD nor does it have a check engine light.
Replaced the Fuel Injection Module but no change.
Checked all fuses with a voltmeter to ensure voltage on both sides of the fuses.
Had the ECM replaced and reflashed, then it wouldn’t crank and pulled a P1631. Did the key relearn sequence and we are back to cranking but not starting and back to no codes on the OBD.
Radio was an aftermarket but still have the original, reinstalled the original radio back in and it says LOCKED (knew it would), and the security light is solid on with the key in the “ON” position.
Not sure where to go next as it’s driving us crazy. Help! Ideas?
Thanks...
Jerome
maxwedge
01-22-2010, 09:44 AM
Welcome to AF, will it start spraying starting fluid ino the intake, got spark to the plugs?
mrjb1923
01-22-2010, 10:47 AM
Yes, sprayed some into the Throttle Body and it wanted to start then for a short time.
Replaced the Fuel Pump.
Replaced the Electronic Ignition Module but no change.
Checked all fuses with a voltmeter to ensure voltage on both sides of the fuses.
Had the ECM replaced and reflashed, then it wouldn’t crank and pulled a P1631. Did the key relearn sequence and we are back to cranking but not starting and back to no codes on the OBD.
Do you think it might be the Crank Sensor??
Taking stabs at fixing it - so ideas are welcome
Replaced the Fuel Pump.
Replaced the Electronic Ignition Module but no change.
Checked all fuses with a voltmeter to ensure voltage on both sides of the fuses.
Had the ECM replaced and reflashed, then it wouldn’t crank and pulled a P1631. Did the key relearn sequence and we are back to cranking but not starting and back to no codes on the OBD.
Do you think it might be the Crank Sensor??
Taking stabs at fixing it - so ideas are welcome
mrjb1923
01-22-2010, 12:36 PM
I just realized that it can't be a Crank Sensor either. We hooked up the Snap-on OBD scanner and were monitoring while cranking and it showing the RPMS of the engine turning over. So scratch that Idea.
maxwedge
01-22-2010, 04:50 PM
Do you have injector pulse when cranking?
consultIII
01-22-2010, 08:59 PM
you should check ignition voltage supply to the injectors. what engine do you have and I'll tell you where to go....err...you know what I mean.
mrjb1923
01-23-2010, 04:07 PM
Using the little test lights, to test the injector pulse.... NO - there is no injector pulse while cranking.
mrjb1923
01-23-2010, 04:08 PM
3.8l engine
maxwedge
01-23-2010, 09:29 PM
AS mentioned do you have 12v at the injector, key on not cranking, if not look at the fuses again.
consultIII
01-23-2010, 10:21 PM
agree with maxwedge
having noid only checks the injector grounding by the pcm. not power at the injectors with key on. If no power to the injector a noid test would fail also. check for power at the injector harness on the pink wire. Should have 12v in run and 0v key off. check more than one injector.
assume that you checked the dfi fuse as replaced the igntion control module?
you don't have injector pulse...what about spark? No spark and injector pulse would direct testing elsewhere.
If have spark and power at injector check the grd side of the injector.
keyk off disconnect the injector harness and ecm black 80pin c1 connector. check continuity for corresponding injector to ecm
inj 1...to ecm pin 43
inj 2...47
3...46
4...42
5...73
6...79
backprobe the harness so you don't wreck the pin fit.
check injector resistance while they're unplugged...should be 11-14 ohms when 50- 90'F temp
having noid only checks the injector grounding by the pcm. not power at the injectors with key on. If no power to the injector a noid test would fail also. check for power at the injector harness on the pink wire. Should have 12v in run and 0v key off. check more than one injector.
assume that you checked the dfi fuse as replaced the igntion control module?
you don't have injector pulse...what about spark? No spark and injector pulse would direct testing elsewhere.
If have spark and power at injector check the grd side of the injector.
keyk off disconnect the injector harness and ecm black 80pin c1 connector. check continuity for corresponding injector to ecm
inj 1...to ecm pin 43
inj 2...47
3...46
4...42
5...73
6...79
backprobe the harness so you don't wreck the pin fit.
check injector resistance while they're unplugged...should be 11-14 ohms when 50- 90'F temp
mrjb1923
01-24-2010, 04:22 AM
Hey GANG... We GOT IT RUNNING.
Before I got the last reply from Maxwedge, we started retracing some of our steps. We ended up reseating the cam sensor (Not crank sensor) and the wire harness to it. When we did, we heard a clicking sound and then the fuel pump kicked in. On a whim, we decided to try and start the car and it started right up. Not sure why this would prevent it BUT I'm willing to bet that SINCE we were moving the wiring around a ground got enabled from the PCM to the injectors. So I suspect that Maxwedge and ConsultIII had actually NAILED it, we just didn't get to this answer before we got the car running. Wiring problems (i.e. Ground problems) are tough to diagnose and you were pointing me to it.
Maxwedge and ConsultIII, my hats are OFF TO YOU!!!
Before I got the last reply from Maxwedge, we started retracing some of our steps. We ended up reseating the cam sensor (Not crank sensor) and the wire harness to it. When we did, we heard a clicking sound and then the fuel pump kicked in. On a whim, we decided to try and start the car and it started right up. Not sure why this would prevent it BUT I'm willing to bet that SINCE we were moving the wiring around a ground got enabled from the PCM to the injectors. So I suspect that Maxwedge and ConsultIII had actually NAILED it, we just didn't get to this answer before we got the car running. Wiring problems (i.e. Ground problems) are tough to diagnose and you were pointing me to it.
Maxwedge and ConsultIII, my hats are OFF TO YOU!!!
maxwedge
01-25-2010, 09:10 AM
Nice to hear it's done, usually retracing one's work will solve the issue.
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