Anyone ever did a crankshaft relearn on a 2005 Yucon? Chevrolet Pick ups are the same I thing. I have a MAC ET9200 scanner.
I installed a new to this 05 Yucon PCM, and set it of for to join the BCM, all when well but PCM is looking for a Crankshaft relearn. No DTCs in PCM but PCM is looking for a relearn. Truck runs great at 19.5 MPG.
Read some of the procedure but not clear on how the scanner drops the RPMs , not a fan of revving up a 300K LS engine to the tune of 4000!
Normally it's just a snap rev once you start the process. Get enginevwater and oil warm.....go through scan tool to start........just throttle to floor till you reach the predetermined rpm and let off...........ecu is just looking at the difference between crank and cam signal...................aka slop in timing chain
I'll be involved in this today. I had misdiagnosed my engine shut off problem and replaced my PCM. I did find the problem later being a ground issue at the left side of the engine that grounds the coil packs. Fooled me because the connection was good and clean but a poor connection under the insulation.
Okay, pulled this off, that engine never saw that high RPM, but was nessary to get the check engine light out! I didn't hold it, I did like you all said and to the mat and off, no DTCs in PCM I could have just put old PCM back in but the new PCM I bought had many up dates that better fuel economy and driveablity. Thank you all for the help and continued follow-up!
4k really isn't that much. Those motors really like being bin that rpm range.........my 6.0l hates towings below 2500..........it wants to run mid 3000 or more.........it most certainly doesn't make big block torque anywhere
