Q: Car will start but won't idle

asked by on October 15, 2016

i am able to start the car but when i dont put my foot on the gas then it will die. it will stay on if you have your foot on the gas and the rpm is over 1000. i have changed out the mass air flow sensor and the air filters. i made sure that all of the connections were there and everything is connected. i also smell gas when the car shuts off

My car has 167000 miles.
My car has an automatic transmission.

This may be a sign of a failing idle air control valve. The idle air control valve is located on or near your intake manifold that monitors the air intake as it is mixed with fuel prior to being injected into the engine. This valve is controlled by the vehicle’s computer which 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. However, when the engine RPM drops below the normal range of 800 RPM (for most cars), it is more than likely that you are dealing with an IAC valve problem. In cases where this valve is clogged or is failing, your vehicle will stall instead of slowing to an idle after the release of the throttle. I would recommend having an expert from YourMechanic come to your home to replace your idle air control valve.

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