Q: When I stop at the stop light or a stop sign my car shuts off.

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I had my computer reprogrammed in November because my car wouldn't start. Then in December my car should like it was idled too high so I got new spark plugs, air filter, spark plug wires, pcv valve, fuel filter on my car because my car was shutting off whenever I stop. I googled and found your website so I booked a service which I thought they would diagnose my car and fix it on the spot all he did was diagnose the car and told me I had various codes and I needed 2 oxygen sensors and that was the reason my car was cutting off. I booked the service and the guy fixed the oxygen sensors and the car was fine when he drove it. I took my car for a ride and it cut off again!! I don't know what else to do? What else could it be?

My car has 195 miles.
My car has an automatic transmission.

It sounds like you may have a dirty or failing idle air control valve. The idle air control valve monitors 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 and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. 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 making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. 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 inspect your vehicle.

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