Skip the auto shop - Our mechanics make house calls

Q: High idling

asked by on

I remove the throttle body and clean, after I done cleaning I put back in the throttle body, then start the engine.when I start engine the idle is 1800 rpm.

My car has 119000 miles.
My car has a manual 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 and 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 mechanic, such as one from YourMechanic, come to your home to replace your idle air control valve.

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: Advice on whether to buy a truck or keep the old one

You've got so much mileage out of that old engine. If I were you I would keep the old one and keep fixing it. Dodge does not make them like they used to. Especially since Fiat has bought them. Now...

Q: Kia Rio cranks but stutters, revs high but won't accelerate

This is not a common complaint and I would speculate the engine has a major vacuum leak or a mass air tube leak between the throttle body and the sensor. I can only recommend having a mechanic, like one...

Q: Surge of acceleration when brake pressed

There is currently no approved safety recalls or Technical Service Bulletins (TSB) for the 2012 RAV4 that address this issue. In the past, there have been 2 recalls, NHTSA Campaign #11V113000 and NHTSA Campaign #10V017000, but these have not been...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...