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Q: Vehicle stalls out after idles down when warm.

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I have replaced the ignition coil, and also just put new wires and spark plugs in it. The vehicle will start-up fine when cold it will run alittle rough. I can drive wherever I need to go. When I shut it off and let it sit for 10 minutes and it will start, but idle down, run rough, and stall. Will have to do that multiple times to finally get it to start and stay running. It only does it when its warm and sits.
My car has 105000 miles. My car has an automatic transmission.

My car has 105000 miles.
My car has an automatic transmission.

A: You may have a dirty or failing idle air co...

You may have 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. 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. It may be possible that the enrichment injector is what is keeping the motor running at cold temperatures since this only works when the engine is cold while warming up. Once the engine is warm this no longer works. At this time, the idle air control valve takes over and may cause the motor to stall if dirty or faulty. 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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