Skip the auto shop - Our mechanics make house calls

Q: Car keeps idling down and shutting off when I drive it.

asked by on

I have two problems. There is a belt in the motor that is making a squealing sound when it is running. Also when I start my car, it starts quick and fast but after about 10 minutes of driving I notice that it starts idling low and shuts off when I come to a stop. When I start it again, it starts up but immediately shuts back off. I have to hold my foot on the gas for a few seconds and then it seems to stay idled up but can still see the RPM hand idling up and down.

My car has 200000 miles.
My car has an automatic transmission.

Hello there and thanks for writing in. Generally belts will squeak when they are loose or not aligned correctly. Occasionally, they may need to have a bit of belt dressing put on them to lubricate them. Your idle issue may likely be related to a dirty or faulty idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and 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!
  1. Home
  2. Questions
  3. Car keeps idling down and shutting off when I drive it.

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: I have a 1996 Chevrolet cavalier and had recently replaced the master cylinder and can't get brake fluid to the back brakes but we

Hi Joan. There are many reasons why brake fluid would not flow to the rear brakes, especially if the vehicle has been sitting for a while. In most cases, when the brake master cylinder is replaced, a lot of air...

Q: Why is the airbag light flashing

Good question. I had the same problem on my truck recently and it was the easiest fix but I will go through a few steps to help you find the issue and hopefully find your problem. First of all,...

Q: Transfer case or transmission

Hi there. If you're hearing a whining noise from the transfer case area, odds are there is either physical damage inside the case or perhaps it is experiencing lubrication issues. In some instances, a damaged inner seal will cause excessive...

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...
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...
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.