Lincoln/Mercury Repair: High idle, mercury sable, throttle plate


Question
Frequently after driving for more than 10 minutes or more my 1997 Mercury Sable idles at arounds 2000 rpm.What could be making it idle this high?

Answer
one simple test is to block off the IAC passage to see if it is that valve. take the tube off from the air filter to the throttle body. there is a hole just before the throttle plate. clean the area with a rag, not a spray. cover the hole with duct tape and use a pin to put a small hole in the tape. reinstall the tube. start the engine and DO NOT touch the throttle pedal. this should be done after the engine is warmed up. if the RPM is under 700 than you need a new IAC motor. if not there is a vacume leak somewhere. dont forget to remove the tape. if it becomes loose and goes into the motor it could get messy and expensive.