Ford
Some 2007 Ford Edge and Lincoln MKX models may turn on the check engine light and store trouble code P0451 in the PCM. If the trouble tree for the code leads you nowhere, the problem is most likely due to electromagnetic interference acting on the fuel tank pressure sensor circuit, Ford said. Installing a new capacitor/jumper harness (part no. 7T4Z-18801-C) into the circuit should eliminate the interference and turn off the check engine light. Detailed installation instructions are included with the harness.
Chrysler
The air conditioning system on some 1997-99 Jeep Cherokee and Wrangler models may work fine for the first few minutes of operation then lose its ability to cool the interior. Chrysler said the system will then often return to normal after the vehicle is allowed to sit for a while, only to lose its ability to cool once again under high system demand.
The carmaker attributed the problem to a frozen evaporator, caused by an out-of-spec low pressure cycling switch. Installing a new-design, better-quality cycling switch should eliminate the A/C woes. Order part no. 05015871AA for 1997 models and part no. 05015872AA for 1998-99 models.
Lexus
Owners of 1997-2000 ES300 and 1999-2000 RX300 models may come into your store with a complaint of a squeak or chirp from the front end when the vehicle is driven over rough or undulating road surfaces.
According to Lexus, one probable cause for the noise is a defective strut mount. The noise can occur on one or both sides of the vehicle. Installing new-design mounts (part no. 48603-33021, RH; part no. 48609-33121, LH) with an upgraded rubber bushing should put the noise issue to bed.
"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].