Hiya fellas, I'm currently struggling with getting my workhorse back on it's feet after removing the engine for resealing and refreshment. It's a 2005 Sierra 1500 2wd, base cab long bed with 370k miles on the 4.8L engine. I believe you folks know this truck as a GMT800, but I'm just learning to speak Chevrolet.
After installing the freshened engine, it starts, runs and drives, but has all of the symptoms of needing a crankshaft position variation relearn. I could numerate the various driveabilities, but I think you fellas are all aware of what those symptoms are. BTW, there are neither those "P", "B", nor "C" codes that are known to inhibit the relearn procedure, nor am I seeing the two "p" codes directly relating to the CKP sensor. Nothing. Zip. Nada.
The specific issue is that neither my Snap-On Verus or my Maximus 2.0 scanners can perform the relearn procedure. The Maximus 2.0 takes me into the procedure, but there is no rev limiter (yikes!), and time after time the procedure does not complete successfully. Meanwhile the Verus won't initiate the test. The scanner displays an error message indicating the test is "out of range" due to the "transmission is not in park or neutral."
Since the range switch is on the side of the transmission, and easy to access, I have tried moving the switch to the limits of it's adjustments, and have swapped in a known good switch. These easy attempts to affect any improvement in the test results proved fruitless. Because the instrument cluster gives correct shift position readings while selecting gears, and is displaying what the ECM is seeing from the range switch, I'm left to believe this is an ECM issue.
This is a puzzle I'm unable to solve all by my lonesome self! Before I head down the road of an ECM repair or replacement, I'd like to hear from the brain trust. Do you guys have any insight as to why the ECM won't conduct the relearn process? Any experience or advise is appreciated. Thanks,
Rick
After installing the freshened engine, it starts, runs and drives, but has all of the symptoms of needing a crankshaft position variation relearn. I could numerate the various driveabilities, but I think you fellas are all aware of what those symptoms are. BTW, there are neither those "P", "B", nor "C" codes that are known to inhibit the relearn procedure, nor am I seeing the two "p" codes directly relating to the CKP sensor. Nothing. Zip. Nada.
The specific issue is that neither my Snap-On Verus or my Maximus 2.0 scanners can perform the relearn procedure. The Maximus 2.0 takes me into the procedure, but there is no rev limiter (yikes!), and time after time the procedure does not complete successfully. Meanwhile the Verus won't initiate the test. The scanner displays an error message indicating the test is "out of range" due to the "transmission is not in park or neutral."
Since the range switch is on the side of the transmission, and easy to access, I have tried moving the switch to the limits of it's adjustments, and have swapped in a known good switch. These easy attempts to affect any improvement in the test results proved fruitless. Because the instrument cluster gives correct shift position readings while selecting gears, and is displaying what the ECM is seeing from the range switch, I'm left to believe this is an ECM issue.
This is a puzzle I'm unable to solve all by my lonesome self! Before I head down the road of an ECM repair or replacement, I'd like to hear from the brain trust. Do you guys have any insight as to why the ECM won't conduct the relearn process? Any experience or advise is appreciated. Thanks,
Rick