Don't worry I am going through the same problem its the TCM or a loose connection ...I simply reset my engine comp. By disconnecting the negative terminal on the battery left it off for around 15 min. Then reconnect it will work few hours later......trans is prob. All right....
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2002 Black Jeep Liberty Sport 4x4
3.7L V6 Engine
Tire size: 255/70/R16 Cooper Dominators
Hidden Hitch / Recovery Hook
Black Brushguard
Recovery gear bag
Front fog/Driving lights
Odometer/ 89593 miles as of 11/28/2012
(OIIIO) JUST SHOW ME THE WAY (OIIIO)