Q: Fast idle - 1983 Mercedes Benz 380SL

asked by on September 08, 2016

My car has a very fast idle when you first start it up. It will idle high. But when you tap on the accelerator the idle will slow down for only a minute. Then it'll go back to the fast idle. Do you know how I can fix this?

Hello. There could be a problem with the throttle cable sticking, causing the high idle. There also could be a problem with the throttle position sensor malfunctioning, causing a high idle. Sometimes a dirty throttle body can cause this problem as well. All of these components should be inspected by a certified technician, like one from YourMechanic, who will be able to diagnose the high idle and make a recommendation for repair.

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