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Q: Idles and stalls again.

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the car is starting quite nicely but does not idle for long before the engine dies. even when you start it and quickly engage into reverse or drive gears from park, it cuts off the engine.

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

Hi There, Depending on when exactly the engine dies, this could be related to a dirty or faulty idle control valve or possible a faulty neutral safety switch. 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.

Your vehicle also has something called a neutral safety switch that will prevent the vehicle from starting when it is in any gear position other than park or neutral. Occasionally, this switch can malfunction causing the car to stall as soon as you put it into any gear. This switch usually also monitors gear selection data as well to transmit back to the computer. This switch is connected to the starter solenoid which allows it to complete the starter circuit only when the transmission is in park or neutral. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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