Check all of the vacuum hoses underneathe the hood. If you have a large enough vacuum leak it could cause the idle to increase as the computer tries to keep the engine from stalling.
Even if the hoses are connected, squeeze them closed with a pair of needlenose pliers, because somtimes the component that the vacuum line is going to can fail, causing a vacuum leak.
Also, if the "check engine light" is on have the computer scanned for codes. A dirty or faulty idle air control valve or other component could cause a high idle. Finally, check to see if the throttle valve is stuck open slightly (this could happen if it's dirty). If it is, you can clean it with carb/choke cleaner and a shop rag (and a little elbow grease). Let us know how it goes.
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Wednesday, April 7th, 2010 AT 8:19 PM