Interesting problem with my car, its otherwise healthy 4R70, and engaging O/D:
Perfect case in point- passing a car on a two-lane road. At 50 or so mph, I'll kick it down first to Third, wait a sec, then down to Second. Blast past the slow car, ease off the gas, it goes into Third... and will not go into OD unless you
- Hit the O/D off switch twice (first to lock it out, then to re-engage)
- Lightly feather the go-pedal, basically forcing the upshift.
When it goes in, there's no slippage. I can't figure this out. I had the throttle body/plenum off the car for cleaning a few months back and I'm wondering if that threw the TPS out of calibration (would this have to do with when it shifts?). I also did my accelerator cable adjustment took slack out of the cable) but seeing as the shifts are electronically controlled I can't see this being the problem.
Ideas? Search revealed no one with a similar issue.
1995 Grand Marquis LS (12/06 to 8/07)
1997 Grand Marquis GS HPP (11/08 to 12/09)
2004 Grand Marquis LS Ultimate (11/19-present)
98k and very, very slowly climbing
It's good to be back.