Some 2004 Dodge Dakota and Ram pickups and Jeep Liberty and Cherokee models with 3.7-liter engines may turn on the check engine light and store coolant sensor trouble code P0116 in computer memory. The code may be accompanied by assorted misfire codes, oxygen sensor-related codes and erroneous codes related to the fuel system, all with no drivability symptoms present. Furthermore, Jeeps with manual transmissions may experience a stumble or hesitation when the transmission is shifted aggressively through the gears.
According to Chrysler, all these issues are the direct result of software glitches in the PCM. Reprogramming the module is the only surefire fix. Check with a dealer for the specifics of the flash.
Owners of 2004-06 Scion xA and xB models may complain of a water leak at the passenger-side footwell. Scion says the problem typically occurs when the air conditioning is on, and may be due to the evaporator drain hose disengaging from the drain tube. Installing a new-design clamp, part No. 88899-52150, onto the hose should hold it in place and prevent further leakage issues.
Before ordering the new clamp, however, get underneath the glove box and take a look at the drain hose. If it's still on the tube, this information doesn't apply; continue troubleshooting until you find the source of the leak. If the drain hose is disconnected from the tube, install the clamp, making sure it's positioned about 1/8-inch from the end of the hose. Next, push the hose onto the drain tube far enough so that the clamp engages the tube. To complete the fix, release the holding clip on the clamp, start the engine, turn the a/c on and verify that the leak has been eliminated.
Some 2007-09 9-7X models with 5.3-liter V8 engines equipped with Active Fuel Management (AFM) may produce a ticking sound from the engine bay on start-up. Saab says the noise typically occurs after the engine has been off for two hours or longer, usually lasts from a few seconds to ten minutes, and is most likely due to a bleed-down condition in the hydraulic lifters. Installing new-design lifters should eliminate the condition in short order.
Be aware that there two sets of hydraulic lifters available, depending on whether or not the AFM system is enabled at the factory. Vehicles built prior to April 1, 2006, have the AFM hardware installed, but the system is disabled. For these vehicles, order new lifters from a set, part No. 12576400. Vehicles built on or after April 1, 2006, have the AFM system enabled. For these vehicles, order lifters from a second set, part No. 12632143.
"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]