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Q: Engine wanting to shut off at complete stops or slowing down lower than 15mph

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okay well i have recently replace all my spark plugs and one coil. My car is still wanting to shut of and stop signs or a light. When i restart the car it struggles to keep on, but once i get above 15 mph its fine? what am i dealing with??? plus my check engine light come on and off like a ghost. i have replace my battery, mass flow senor, turbo case, crack shaft sensor as well all in the past month

My car has 17000 miles.
My car has an automatic transmission.

Hi There! It sounds like you may have a dirty or failing idle air control valve causing your engine idle to fluctuate and eventually stall. The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher load of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. The idle air control valve helps to control the deceleration back to an idle. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.

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