Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Tech left oil cap off and now car won't start

Hi there. Your oil cap will keep oil from splattering in your engine bay when started. It is possible that a large amount of oil has exited from this opening causing your vehicle to shut off. Also, the oil pressure...

Q: Timing off or plugs need replacing

Hello. The timing on your vehicle is not adjustable and should not be a problem. Most of the time this is caused by worn out spark plugs or a sensor that is not reading correctly. I would typically start by...

Q: Car stopped, steering wheel stuck, check engine light orange

It sounds like you may have a failing alternator. The alternator is responsible for running the electrical system of your vehicle while the engine is running as well as keeping the battery fully charged. If the alternator fails, this can...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...