Having problems with your Cars & Trucks ?
2000 Ford Contour SVT engine idles high (revs) when driving
\015 First off there is a P0420 code "Catalyst System Efficiency Below Threshold (Bank 1)" which I don't believe is related. When I take my foot off the gas while driving down the road at say 30 to 50 MPH and push the clutch in or put the trans in neutral the engine will "idle" at sometimes 1500 rpm sometimes 2500 rpm or higher. I don't even have to take it out of gear. Foot off the gas and acts like I have it in cruise. The problem is intermittent, weather(wet/dry/cold/hot), engine cold or hot doesn't make a huge difference. It does idle down slowly when I come to a stop though. The problem is intermittent and I can go for weeks without a problem. For no apparent reason it will start acting up again. Bad sensor or connection problem? I have been working on my own cars for 25 years but this problem I have not seen. Looked for a vacuum already, none found.\015
It sounds like a faulty idle air control valve. The computer uses the valve to control idle speed by regulating the amount of air entering the throttle body. Its possible the motor inside the valve is weak, or the valve is gummed up. I would unplug the valve when base idle is near normal and drive it for a day or two. If the valve is the problem the idle speed should stay in one place. And it should set a trouble code for the valve being disconnected.
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