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Q: Car is chugging at low speeds and then stalls when I stop.

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My car started to chug at low speeds, i didnt notice it jerking forward at all but when i applied the brakes or let off the gas i could feel it chugging. This only happened when i was below 15 mph and i havent noticed it at higher speeds. when i came to a complete stop the car stalled. I put the car into neutral and it started fine but once i got to low speeds again it started to chug again.

My car has 98000 miles.
My car has an automatic transmission.

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. This is all controlled by the idle air control valve. When the engine RPM drops below the normal 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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