Just out of curiosity, how (if at all) does the throttle body motor tie into this? I recently had it replaced when the car did not want to stay running at all. That did the trick, but now that I am again having a problem ( two months later) I wonder if the part that they used is in some way defective and causing me this additional headache. Your assistance is appreciated.
Idle Control System Malf - Additional information please on 2003 Toyota Highlander
by Stett in Ann Arbor, MI on February 19, 2009
ANSWER by patrick mannion , February 19, 2009
Your engine uses an idle air control motor (IAC) it is just under the rear air induction duct just at the throttle butterfly housing. On several Toyota and Lexus products these IAC devices "gum up" with carbon, many people just replace the valve I have taken many of them apart and cleaned them with Chemtool. If the IAC fails it normally causes the engine to stall on a cold start in the morning or stall when approaching a stop sign with electrical loads on. it normally doesn't make an engine not run. A failed air flow meter will make a car not run but these usually set a Check Engine light for random misfire or result in sluggish performance. Has your car set a Check Engine Light?