Terri Larkin called on 11/17 about her Caravan acting like it was in neutral when she put it into gear and then jumping abruptly. She solved the problem by turning it off and back on. I think her problem might be the Speed Sensor b/c my Ford Taurus did the same thing for years: When put into gear, doesn't move and revs like in neutral, then suddenly jumps into gear sometimes. Problem could sometimes be solved by turning it off and on or moving gear shift to park and then back to drive. Also, even after warming up, when starting from a stop it would stay in 1st gear and not shift up, then suddenly shift up and car would jerk forward. Sometimes when it wouldn't switch gears the RPMs would remain high, even on highway. We thought we needed a new transmission! We found on line that it might be the speed sensor, which lets the car know what speed you are going. We switched it out and all the problems disappeared!