I want you to try one more thing before we move on to the PCM. We are going to reteach the computer what it should be doing. It is called the relearn process.
Disconnect the battery. If you can, let it sit overnight. NOTE: There will be driveability problems until the computer relearns everything.
1) Replace the battery
2) Start the vehicle in park and allow it to warm up to normal operating temp.
3) In OD, moderately accellerate to 50 MPH (if it shifts) for a minimum of 15 seconds. It should be in 4th gear
4) While holding the speed steady, lightly apply the brakes and release them after about 5 seconds.
5) Pull over and park for at least 20 seconds with the engine running and the trans in drive
6) Repeat this process 5 times.
I hope this helps. If there is engine driveability problems, the relearn is to drive the vehicle for 10 miles + to allow for relearn
Let me know what you find and if this helps. I'll keep my fingers crossed.
PS: You're not overlooking anyting. It's the nature of the beast.
Thursday, January 21st, 2010 AT 7:08 PM