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Q: Check engine light and car idles low/runs differently

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Check engine came on, hesitated to start and when accelerating car hesitates to push while driving. Also idles low. Had full maintenance about a year and a few month ago including spark plugs etc a complete tune up, spent nearly $2k in repair. What could be the problem?

My car has 153000 miles.
My car has a manual transmission.

A: This may be related to a dirty or failing i...

This may be related to a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle's computer which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed. When the engine RPM drops below the normal idling range of 750-800 RPM (for most cars), this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your idle air control valve.

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