Lexus Repair: 1999 ES300 Starts cold, trouble starting when warm, lexus toyota, toyota service

Question
Hi,
I've had this issue for about a month.  The car will start fine when it's cold but have trouble starting when warm.  The RPMs will go up like it's starting then quickly die if I don't press the gas.  I can keep it running if I hold the gas pedal down but obviously can't get it into gear.  Took it to an independent shop and they can't see any codes on the computer so it looks like it is dead.  They did mention that air intake valve that could get stuck.  It has recently started doing while actually driving which is dangerous. What should I do?

Answer
I would take a look at the IAC(Idle Air Controller) located by the throttle body.  Remove the unit and give it a good clean. Carbon deposit would cause this particular problem on ES an RX300.  

JP importz
Dallas Indepedent lexus & Toyota
Service, Repair and Performance
www.jpimportz.org