2001 S-Type 4.0 L new problem. The shifter will not physically move to 2nd or 3rd position. When moving shifter to park sometimes have to go back to reverse and then to park for it to engage. Recently when shifting to drive the trans does not engage, have to move it to 4th till it engages and then back to drive.
Second problem it just recently started slipping between gear shifts. I can feel the slip and the tach also indicates the slip. Never had a problem like his before; hoping clutches aren't worn out. It started doing this all of a sudden. One thing I noticed was I had just put a Magellan GPS and plugged in cigar lighter. Sometimes it wouldn't come on at all and sometimes would act really funny and display garbage. I unplugged it thinking it might be causing some computer problems. Haven't driven it since I removed the GPS as I have on my lift to check and clean shifter switch, cable, and fluid level.
I read the threads available on this topic but none addressed the slipping between shifts. Any help with these problems would be greatly appreciated. Thanks
2001 S-Type 4.0L
1988 XJ40
2003 Toyota Avalon
2003 Chevy Silverado K3500 Dually Diesel

 

Check the fluid level or change it if hasn't been done recently enough.

 

When I read this, my first thought is your GPS unit is fine but there is a power supply problem. I'm thinking low or high voltage, or even AC ripple. Could such a problem also cause the transmission to act up? Not super likely, but try the GPS in another car and see if it behaves there.

I'd also suggest checking the shift cable. Find an empty parking lot, such as a theater showing a Michael Moore film. Engine idling, play with the N position. Carefully release your foot from the brake and confirm nothing happens, meaning the transmission really is in neutral. If the car tries to move in either direction, it was actually in gear. That would suggest the cable is stretched or out of adjustment.

Next step is checking the fluid level, as JagV8 suggested.