I have a 99 WJ. It's doing something weird that I can't put my finger on. When I first start down the road with my WJ the speedometer doesn't work. Then it starts jumping around and at the same time it starts shifting back and forth between gears. Then after a little bit the speedometer starts working fine and the shifting issue stops. Then after driving for a while the speedometer will either go back to zero or start bouncing all over the place and the shifting issue starts back up again. I'm lost. Any help would be great. Thanks.

 

Any codes? Sounds like a speed sensor going out. That will control shifting also.

 

Yep, sounds like a vehicle speed sensor problem.

 

Engine light is on but it stays on because the catalytic converter is gone so I didn't figure I'd get a good reading on codes anyway. I wasn't sure if the speed sensor would cause it to keep shifting or not. I'll check that. Thanks guys.

 

Thru AutoZone there is a Transmission Speed Sensor in the parts listing and a Speed Sensor in the accessories. Which one would it be?

 

my speedometer is acting strange as well but i havent had the shifting issues u spoke of. i thought it might be just the instument cluster. is there a way to check the speed sensor u guys are talking of? i cant find anything in my repair manual.....

 

It on the transmission.