Q: Car idles high at startup

asked by on February 09, 2016

My car idles high when I start it.

The idle air control valve on your car may be defective, causing the high idle. A couple of checks would need to be done to determine if this is the case. Your engine needs to be checked for any vacuum leaks, and then the idle air control valve should be checked for carbon sticking valve, and throttle body open. If all of these are okay, then the valve should be checked to be within specifications, electrically. I recommend a mechanic, such as one from YourMechanic, run a detailed inspection of your vehicle’s high idle speed.

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