Skip the auto shop - Our mechanics make house calls

Q: Car will start but won't idle

asked by on

i am able to start the car but when i dont put my foot on the gas then it will die. it will stay on if you have your foot on the gas and the rpm is over 1000. i have changed out the mass air flow sensor and the air filters. i made sure that all of the connections were there and everything is connected. i also smell gas when the car shuts off

My car has 167000 miles.
My car has an automatic transmission.

A: This may be a sign of a failing idle air co...

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. I would recommend having an expert 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

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: Turns over but wont start

A no start diagnostic would reveal the cause. Try holding the accelerator pedal to the floor and cranking the engine. If the idle air control valve is stuck closed and/or the intake air charge is insufficient, the vehicle should start...

Q: Heater blowing cold air

Hello there, a variety of faults will cause your 1998 Ford Taurus to blow cold air when the heater is on. Some of the more likely issues are the vehicle is low on coolant, Air blend door actuator fault, failing...

Q: 1990 Porsche 944, starts well, shuts off after a few minutes

After checking for the proper fuel pressure, have an experienced technician inspect the ignition systems, crankshaft position sensor and distributor pickup coils. A malfunction here will cause a stall, as these devices help the computer determine when to send spark...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.