Q: When i have my car running with my heat or ac on my car hesitates like it wants to stop when i'm stopped at a light.

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When I have my car running with my heat or ac on my car hesitates like it wants to stop when I'm stopped at a light. Sometimes it does cuts off when I'm waiting at a light, then I have to put it in park then start it back up. What will it be?

My car has 192000 miles.
My car has an automatic transmission.

As you may know, your car’s AC system when working properly puts an extra load on the engine at all times when it is running. When this happens, your car’s computer makes adjustments to compensate for this extra load on the engine. There is a component in your engine’s intake system called an idle air control valve that helps to control air intake as it is mixed with fuel during idle or low speeds. When this is dirty or not working properly (especially under load from additional power required for the AC), tis may cause incorrect adjustments to be made to the fuel mixture causing the hesitation you describe. I would recommend having an expert from YourMechanic come to your home to take a look at your car to properly diagnose and repair your idle air control valve.

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