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Proper diagnosis of that problem usually requires a trained technician with access to the ODB-II port. By interpreting the codes produced under controlled test conditions, they can usually narrow the problem to an electrical, vacuum, or fuel fault. In extremely difficult-to-diagnose cases you may need a GM World Class Technician. Ask your dealership if a WCT is available on their staff or from another dealership in the area.
The dealer in our area has a guy that is supposed to be the absolute best in the area on GM electronics, has to been to bout every school they have on the topic, but WTC i'm not sure if he is that level or notOriginally Posted by Eritosthenes
Power and grounding are absolute. If they're not 100% dead solid perfect, you can't trust the results of any other troubleshooting or diagnostic tests. The trouble with O2 sensors is that they're almost never the direct cause of a problem. More often than not, they are accurately reporting the results of an air/fuel stochastic problem upstream.Proper diagnosis of that problem usually requires a trained technician with access to the ODB-II port. By interpreting the codes produced under controlled test conditions, they can usually narrow the problem to an electrical, vacuum, or fuel fault. In extremely difficult-to-diagnose cases you may need a GM World Class Technician. Ask your dealership if a WCT is available on their staff or from another dealership in the area.
Installed the new computer yesterday and not surprisingly it did not fix it, but however today they got down to the technical stuff and on the data link connector they found a white wire with a purple tracer on it that is the "ground" for this part of the car, it was damaged or exposed they said, so long story short the PCM could not communicate because it was not grounded properly, so two 02 sensors, a PCM, and 700.00 I'm back to good
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Nothing like a shop just throwing parts at it without a proper diagnosis. Originally Posted by trooper22
Installed the new computer yesterday and not surprisingly it did not fix it, but however today they got down to the technical stuff and on the data link connector they found a white wire with a purple tracer on it that is the "ground" for this part of the car, it was damaged or exposed they said, so long story short the PCM could not communicate because it was not grounded properly, so two 02 sensors, a PCM, and 700.00 I'm back to good
Glad you got it resolved.
I don't know what the problem is. But, I have found many years ago that in the fall I clean both ends of the battery cables and battery posts and other grounding points as part of the storage regimen.
There is a lot of draw on modern vehicles and sufficient grounding is a major issue.
I have corrected problems on my motorcycles with cleaning all the grounding points and adding some.
There is a lot of draw on modern vehicles and sufficient grounding is a major issue.
I have corrected problems on my motorcycles with cleaning all the grounding points and adding some.
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Glad they got to the bottom of it and you can enjoy the car now Originally Posted by trooper22
Installed the new computer yesterday and not surprisingly it did not fix it, but however today they got down to the technical stuff and on the data link connector they found a white wire with a purple tracer on it that is the "ground" for this part of the car, it was damaged or exposed they said, so long story short the PCM could not communicate because it was not grounded properly, so two 02 sensors, a PCM, and 700.00 I'm back to good
Those grounding problems will getcha every time
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just wondering if this fixed your flickering lights issue as well. Originally Posted by trooper22
Installed the new computer yesterday and not surprisingly it did not fix it, but however today they got down to the technical stuff and on the data link connector they found a white wire with a purple tracer on it that is the "ground" for this part of the car, it was damaged or exposed they said, so long story short the PCM could not communicate because it was not grounded properly, so two 02 sensors, a PCM, and 700.00 I'm back to good
just where is this data link connector?
