This problem started with the idle at 4,000rpm. I replaced the throttle control sensor which made no difference. I removed the throttle body, cleaned it out with carb cleaner, especially where the IAC comes in (I think that is where the main problem was). I checked vacuum lines. I replaced the gasket, changed the spark plugs, wires, air filter, and oil, but it is still idling from between 1,000 - 1,600. How do I get it to idle at 800rpm? Is there something else I can do. The check engine light is on, when it goes through the test, it pretty much says there is an issue, but not specific. Where should I look next? If there is a vaccum line that would most directly impact this, which one would it be? Thanks for your help guys!