Ford Repair: Taurus 97 fast idle, air control valve, vacuum line

Question
My 97 Taurus has begun to idle at 2,500 rpm even when warm. If I put it in neutral when stopped for a traffic light, idle goes up to 2.5k rpm. Otherwise, engine runs well and smooth. Any probable suspects?

Answer
Look for either a broken/missing vacuum line.Clean and or replace the idle air control valve.Clean the throttle body thoroughly,in particular the butterfly valve.Very detailed instructions are on previous posts dealing with idle issues.Is the check engine light on?If so have the codes read.