Acura reports that some 2013 RDX trucks may intermittently illuminate the Check Engine light and log trouble code P3400 and/or P3497 in the PCM. One probable cause for the trouble, said the carmaker, is a sticking rocker arm oil pressure switch. The problem can occur on one or both banks of the engine. Installing a new-design pressure switch and O-ring (part No. 37240-R70-A04 and 91319-PAA-A01, respectively) should eliminate further trouble.
Before ordering the new parts, however, check the engine oil dipstick because a low oil level can cause these codes to set. If the oil level is low, add oil, clear the code(s) and release the vehicle to the customer. If the oil level is okay or the truck comes back with the same complaint, replace the front and/or rear pressure switch and O-ring, depending on the code(s) logged. For reference, the location of each rocker arm oil pressure switch is shown in the illustration above.
Owners of 2002-03 3.9L Dodge Dakota pickups with 42RE automatic transmissions manufactured before Nov. 22, 2002, may come into your store with a complaint that the transmission won't shift out of second gear when climbing hills or steep grades.
According to Chrysler, if there are no trouble codes stored when the problem occurs, it's likely due to software anomalies in the PCM. Reprogramming the module with updated calibration files is the only reliable fix. Check with a dealer for the specifics of the flash.
Volkswagen reports that it's perfectly normal for the electric cooling fans on its 2005-10 models to continue running for quite a few minutes after the engine is shut down. To be more specific, the fans can run for up to 15 minutes on vehicles equipped with gasoline engines; up to 16 minutes on vehicles with diesel engines. Make a note of the prolonged runtime or you just might be chasing problems that don't exist!
"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].