Skip the auto shop - Our mechanics make house calls

Q: Shuts down when idling

asked by on

My car shuts off while idilling or sometimes while driving

My car has 255000 miles.
My car has an automatic transmission.

Hello There, What you have described sounds like you may have a dirty or faulty idle air control valve. The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher dose of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.

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: Running lean

With the fuel pressure low by 10 psi and leaking down indicates the pump in the tank or the pressure regulator is leaking down pressure. You will need to isolate the pump by blocking return line to see if pressure...

Q: Truck has trouble starting, idle's too low, losing power, check engine light is on.

You may want to try and run some combustion cleaner into the intake. You can get the good cleaner from any Ford parts store. You use a small rubber hose and allow it to get sucked into the engine slowly...

Q: Will not crank

Hi, thanks for writing in. It sounds like your alternator may have failed. If your vehicle died on the highway and will not even crank the starter now, it is likely that your battery is fully discharged. The only way...

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...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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...