Some 2005-06 2.8-liter Jeep Liberty sport-utility vehicles built before Nov. 21, 2005, may produce strange driveability and/or braking issues at altitudes above 5,000 feet.
Among the customer complaints a service advisor might hear are that the engine won't hold an idle after startup, the engine shakes during warm-up and/or that the check engine light is on with trouble code P0504 (defective brake switch) stored in the powertrain control module (PCM).
According to Chrysler Group L.L.C., all of these symptoms are the result of software incompatibility issues in the PCM. Having the module reprogrammed with updated calibration files should eliminate further trouble. Check with a dealer for the application specifics.
Some 1998-2002 Ranger pickup trucks may produce a hoot- or moan-type sound from the clutch as the transmission is shifted.
Ford Motor Co. said the noise usually reaches its peak just before the clutch pedal comes to the top of its traveland is most likely due to resonance from the pressure plate just before clutch engagement.
Installing a new-design clutch disc and pressure plate should result in a permanent fix. For the disc, order part #2L5Z-7550-AARM for 2.3- and 2.5-liter engines; and part #2L5Z-7550-BARM for 3-liter engines. The pressure plate is identical for all three engines, and it goes by part #2L5Z-7563-AA.
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] For more Factory Fixes, go to www.tirebusiness.com and click on the Service Zone icon.