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Q: Whats causing my car to cut off in slow moving traffic

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Whats caising my car to cut off in slow moving traffic and when it does my car sarts write back up.only happens when driving in slow traffic

This is a common sign of 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. In your case, when driving in slow traffic, if this valve is dirty or faulty it may struggle to maintain the proper air/fuel mixture resulting in it stalling as you have described. Since this valve is controlled by the vehicle’s computer, it 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 with the help of the idle air control valve. When the engine RPM drops below the normal range of about ~800 RPM, 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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