LY6 conversion e38 ECM initial start problems
02-16-2016, 10:44 PM
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LY6 conversion e38 ECM initial start problems Working on a conversion in an 85 chevy truck, using a 08 LY6 with, 6L80e trans. Used a new GM wiring harness form an 09 GM truck with a 5.3. Had to add the camshaft sensor wires to the harness because the but has a 5 wire plug. The ecm was taken in to a local tuner to have VATS deleted.
Engine would not start. Had no spark and no injector pulse. When crank was in just the right position I could we a spark from number one coil when I plugged the coil harness back in. All wires were checked and rechecked. Good grounds. Ecm is grounded. 12 volts checked out. I had crank signal, could see it up to 180 rpms during start cranking on my otc scanner.
Camshaft signal present, could see the counter going up on scanner while cranking.
Even tried grounding the "start enable" wire for the starter circuit in case the tuner missed it.
My diagnosis was that the ecm was bad, or the VATS wasn't disabled correctly, so the ecm went back to tuner.
Tuner said the "firmware was corrupt" so it was reflashed.
Ecm was brought back and hooked up again with the same results. No spark and no injector pulse. And now it is throwing a DTC p0633, "theft deterent key not programmed".
Spoke with shop that did tuning and they said I need to do a crank relearn. Well if I can't start this engine I can't do a crank relearn??
And they also said I would need to do a security relearn. I don't have the body control module hooked up so that's not going to happen either.
The only other codes present are emissions and fuel tank related.
So if anyone has some suggestions it would definitely be appreciated.
Engine would not start. Had no spark and no injector pulse. When crank was in just the right position I could we a spark from number one coil when I plugged the coil harness back in. All wires were checked and rechecked. Good grounds. Ecm is grounded. 12 volts checked out. I had crank signal, could see it up to 180 rpms during start cranking on my otc scanner.
Camshaft signal present, could see the counter going up on scanner while cranking.
Even tried grounding the "start enable" wire for the starter circuit in case the tuner missed it.
My diagnosis was that the ecm was bad, or the VATS wasn't disabled correctly, so the ecm went back to tuner.
Tuner said the "firmware was corrupt" so it was reflashed.
Ecm was brought back and hooked up again with the same results. No spark and no injector pulse. And now it is throwing a DTC p0633, "theft deterent key not programmed".
Spoke with shop that did tuning and they said I need to do a crank relearn. Well if I can't start this engine I can't do a crank relearn??
And they also said I would need to do a security relearn. I don't have the body control module hooked up so that's not going to happen either.
The only other codes present are emissions and fuel tank related.
So if anyone has some suggestions it would definitely be appreciated.
