Skip the auto shop - Our mechanics make house calls

Q: Can bad idle air control valve cause problems at highway speeds?

asked by on

Idle became erratic and engines shuts off and on at speed. Problem is intermittent and does not show check engine light
My car has an automatic transmission.

As you know, the idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. When the engine RPM drops below the normal range of 750-800 RPM (for most cars), this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. Depending on the severity of how dirty the valve may be (in your case, maybe not enough to register the check engine light), this may be intermittent or erratic. Although normally the idle air control valve monitors air intake at low or idle speeds, this may affect the the functionality of it in the case of driving down the highway and quickly letting off the gas pedal. As you know, part of the job of the idle air control valve is to slowly bring the engine down to an idle or low speed when reducing engine RPM’s. I would recommend having an expert from YourMechanic come to your location to diagnose and repair 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

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: Van idles rough

Your car has a small purge valve that controls the venting of fumes from the fuel tank as these fumes build up inside, particularly when you are refueling the car with gas. The EVAP system prevents fuel vapors from the...

Q: Will a supercharger blow my motor?

Hello There! A supercharger can be a great horsepower addition, however some things to keep in mind are things like fuel octane requirements, cooling issues and fueling and timing corrections. As you know, when adding a supercharger, you are creating...

Q: What's is wrong?

This may be a result of a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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...