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Q: Rough idle when stop on D mode...

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sir i have Toyota Vitz 1.0 2011 model..all the things is ok it has great pick every thing is perfect on running but when i stop on signal on D mode than its start idling or i use power window on stop than it still idling...i do all the tuning plug change filter change but problem still there tell me the best solution... My car has 45000 miles. My car has an automatic transmission.is this a electric throttle body issue or something else thanks

My car has 45000 miles.
My car has an automatic transmission.

A: Hi there. This may be a sign of a failing i...

Hi there. 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. A professional from YourMechanic can come to your car’s location to diagnose the rough idle and replace your idle control valve if deemed faulty.

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