Archived Transmission Drops out of OD Momentarily

[DWSkillman]

My Dad and I own TD's with automatic trannies. Mine is 2002, his is a 2000 I believe. Last year I had a problem for a couple weeks where the transmission would drop out of overdrive momentarily, then go back in. I think it was about a 200 RPM increase when this happened. I took it to the dealer, they said it was a bad ground problem. They wiggled wires, tightened ground straps, but th eproblem persisted fro another week or so, then corrected itself. My Dad's truck is currently in southern CA, where things have been kind of moist this winter. His truck has developed the same symptoms. He's more of a tinkerer than I and has ben underneath, wiggling and tightening and reseatign every wire he can find, but to no avail. Does anyone have any ideas on this? It's driving him nuts! Thanks for any help on this. Does anyoje know anybody in the Indio/Palm Springs area he could take the truck to?

Doug

 

[AKAMAC]

Does it do it at around 45 MPH? If so then you will need to put a noise filter on wire # 31 of the PCM. You can also try running a temporary ground from the battery to a T/C inspection cover bolt to see if that fixes it.

 

[CarlJensen]

Do a search on "TPS Cleaning", "OD lockup" or "TC lockup". You will find a lot of info on the subject. The TPS can cause this problem as can noise in the system. As AKAMAC said, a filter can help as well as pulling the TPS wires out of the original loom and rerouting them. Dirty TPS is a common prob also. Sometimes the brake switch will also give problems if it is out of adjustment or loose. Do a search and you will get a lot of info on this subject.