Lexus Repair: high idle, toyota highlander, lexus dealer

Question
My 2000 RX300 revs up to 1,800 when the engine is started totally cold.  That started after the Lexus dealer gave it 60K service last June.  When I took it in last week to get the problem fixed they replaced the IAC valve for $517, but that didn't change anything.  I think the dealer is clueless, in fact, before they replaced the valve, they tried to convince me that the high idle was normal.  What do you think I should look at next, or should I just forget about it and live with the high idle.

Answer
It is normal. The ECU will idle whatever it wants. The dealer was not clueless. They told you right in that the idle is fine. you sorta talked youself into giving them about $400.
You can generally clean the throttle plate, IAC & EGR valves with a descent spray cleaner & a brush. It's routine maintenance on a vehicle with an EGR system. (The carbon from the exhaust eventually sticks the previously mentioned valves.)

On a personal note. You've got a Toyota Highlander. Unless you have warranttee service, go to a Toyota dealer. You don't get to go pee in the marble lined bathrooms, but aleast you'll pay 1/2-2/3 the cost to do so. ;)
Just kidding!