My 2002 grand Cherokee laredo runs great except everytime my truck is turn off and started the overdrive doesn't work ie..ill drive to the store and my rpms at 65 mph are around 2 k then on my way back after I turned off and restarted its at 3 k at 65 mph ..so I will shift to neutral and shut off and restart then shift back into drive and it starts working again any advice would be appreciated thanks ,
Bryan

 

scan it for codes. I know the older GC wouldnt shift to od till a certain temp was reached

 

Ok the codes read throttle positioning sensor low voltage malfunctioning 3 oxy sensors high voltage misfiring all six cylinders powertrain control modul malfunctioning I'm thinking the tps is causing all the malfunctions

 

Ouch! Looks like you've got some work to do.

 

Well I changed the throttle position sensor and it fixed everything it drives like a new truck and all the codes are gone