Some 2002-06 RSX cars and 2007-12 RDX SUVs may turn on the Check Engine light and store trouble code P2646 or P2647 in the PCM. Acura reports that the problem is usually intermittent and may be tough to duplicate once the trouble code is cleared with a scan tool. A defective rocker arm oil pressure switch is the most likely cause of the malady. Installing a new-design pressure switch and O-ring (part No. 37250-PNE-G01 and part No. 91319-PAA-A01, respectively) as shown in the illustration above should eliminate the trouble immediately. When installing the switch, make sure it's tightened to 16 foot-pounds to fully compress the O-ring.
Chrysler reports that the oil change monitor on some 2008 Aspen SUVs may come on prematurely, sometimes right after the oil was changed and the monitor was reset.
According to the carmaker, the condition is usually intermittent and frequently occurs right after the battery was disconnected for other service. A software glitch in the PCM is ultimately to blame for the anomaly. Reprogramming the module with updated calibration files is the only surefire fix. Check with a dealer for the specifics of the flash.
Drivers of 2008 F-Super Duty pickups may come into your store with a complaint of a thumping sound whenever the air conditioning compressor engages. According to Ford, the noise typically affects trucks built before July 20, 2007, and is most likely due to design defects in the suction-side accumulator. Replacing the accumulator with an upgraded unit should eliminate the annoyance. Order part No. 8C3Z-19C836-D for trucks with gasoline engines; part No. 8C3Z-19C836-C for pickups with diesel engines.
"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].