Some 2005-08 Avalon, 2006-08 RAV4, 2007-08 Camry and Sienna and 2008 Highlander models with 3.5-liter V6 engines may produce a squeaking sound from the engine compartment when the engine is idling. One likely source of the noise, reported Toyota, is a worn No. 2 idler pulley. Replacing the idler pulley with an updated design (part No. 16604-0P011) and adding an extra pulley cover plate (part No. 16649-31020) should eliminate the noise in short order.
Referencing the accompanying illustration, notice that there are two No. 2 idler pulleys shown. Avalon, Camry and Sienna models use both, so you'll have to double up when ordering the new-design pulley. RAV4 and Highlander models have electric power steering, so they use just one No. 2 idler pulley—the one on the lower right in the illustration.
Also note that each No. 2 idler pulley is sandwiched between two cover plates. The plate to the outside of the pulley already comes on the engine. The plate to the inside of the pulley is the extra one that needs to be installed to ensure that the squeak is eliminated. Order two extra cover plates for Avalons, Camrys and Siennas; one for RAV4s and Highlanders. After the new pulley(s) and extra cover plate(s) is installed, tighten the attaching bolt(s) to 40 ft.-lbs.
Some 2007-09 ES350 sedans and 2007-2010 RX350 SUVs with the 2GR-FE V6 engine may turn on the Check Engine light and store trouble code P0505 in computer memory. One likely cause, reported Lexus, is a bad idle air control (IAC) motor. Replacing the throttle body assembly (which includes the IAC motor) with an updated unit should eliminate further trouble.
Before ordering the new throttle body, however, hook up a scan tool and look for codes other than the P0505. If you see any, take care of them first. If the only code logged is the P0505, check the PCV and air induction systems for leaks or loose connections. If both systems are tight, go ahead and install the updated throttle body, part No. 22030-0P050, using a new gasket.
"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]