Pirrofab
15+ Year Contributor
- 726
- 40
- Sep 2, 2006
-
gouldsboro,
Pennsylvania
6 bolt /1g harness in a rwd project. everything worked fine until i replaced the motor and "cleaned up the harness " a bit by removing some wires not in use, ( emission connectors, power steering, etc) . the harness is getting old and brittle, a few old splices/repairs near the ecu connector and the injector harness has been repaired with new connectors and pigtails.
go to fire up new motor and it runs for about 2-3 seconds and shuts off, no throttle response despite seeing it in link , its recording air flow, no codes. coolant temp good. this repeatedly runs for 2-3 seconds and dies and also has a misfire. i swap injectors and check everything in link thinking i have something funky in the tune (and swapped injectors back to stock because it was one less variable before i checked spark) I verify no spark on cylinders 2/3 suspect faulty coil because its easy and simple. no change. very no input to coil on 2/3 worked back to ptu. no input to ptu from ecu telling the ptu to fire the coil. verify continuity to ecu. at this time switch to a spare cas for testing by hand instead of constantly cranking the motor wearing down the battery. spare cas also confirms no spark on 2/3 but 1/4 are fine and so is injector pulse. un tape harness for visual inspection and perform continuity test from cas to ecu. all checks ok but did find one splice at white wire on cas that looked old so it was cut out and replaced anyway. now that the harness has been fiddled with on both engine and ecu side i test with spare cas again and now have working coils. swap back to original cas and hit the key and the car now runs on all 4. As i button up some odds and ends my next test will be to get the car outside and while its running i'll be doing a tap and wiggle test on the harness to try and re duplicate this issue.
go to fire up new motor and it runs for about 2-3 seconds and shuts off, no throttle response despite seeing it in link , its recording air flow, no codes. coolant temp good. this repeatedly runs for 2-3 seconds and dies and also has a misfire. i swap injectors and check everything in link thinking i have something funky in the tune (and swapped injectors back to stock because it was one less variable before i checked spark) I verify no spark on cylinders 2/3 suspect faulty coil because its easy and simple. no change. very no input to coil on 2/3 worked back to ptu. no input to ptu from ecu telling the ptu to fire the coil. verify continuity to ecu. at this time switch to a spare cas for testing by hand instead of constantly cranking the motor wearing down the battery. spare cas also confirms no spark on 2/3 but 1/4 are fine and so is injector pulse. un tape harness for visual inspection and perform continuity test from cas to ecu. all checks ok but did find one splice at white wire on cas that looked old so it was cut out and replaced anyway. now that the harness has been fiddled with on both engine and ecu side i test with spare cas again and now have working coils. swap back to original cas and hit the key and the car now runs on all 4. As i button up some odds and ends my next test will be to get the car outside and while its running i'll be doing a tap and wiggle test on the harness to try and re duplicate this issue.
