Skip the auto shop - Our mechanics make house calls

Q: RPM revs too high

asked by on

My car has a problem with the rpm. When in idle it revs to about 2000 rpm and that's when the compressor kicks out. When the compressor kicks in it goes down back to 1200 rpm which is really high.

My car has 188000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. This is a sign of a failing idle air control valve. This is a unit that 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 nearing its replacement age, your vehicle will stall instead of idling after the release of the throttle. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this rough idling issue for you, and make or suggest any repairs as needed.

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
  1. Home
  2. Questions
  3. RPM revs too high

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: Why does my car shake at 60 mph

The tires, tie rods, and rack and pinion are the most common areas to look at for a vibration in the front end. The tires may be out of balance or have a stop leak inside one of them. The...

Q: Car deck

Hi, thank you for writing in. I am assuming you are talking about the radio. When installing a new radio, it really depends on what brand/type of radio you will putting in. A lot of manufacturers will have a plug...

Q: Shaking and stalling during low idling

There are no common issues that would cause this problem - especially with the relatively low mileage. I recommend testing the computer for codes causing the stalling you have. If the computer sees the stall, it should set a code...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...
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...