Owners of 2009-10 Jeep Compass and Patriot models with 2.4-liter engines and automatic transmissions may complain of a bump or jerk from the transmission under the following driving conditions: Between 25 mph and 30 mph just as the driver lifts his foot off the accelerator, then again as the vehicle slows to about 15 mph while coasting.
The bumping or jerking sensation will also occur at between 3 mph and 15 mph just as the driver begins to put his foot into the gas pedal to accelerate.
According to Chrysler, all these transmissions issues are due to software anomalies in the PCM. Reprogramming the module with updated calibration files is the only surefire remedy. Check with a dealer for the specifics of the flash.
"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected].