Skip the auto shop - Our mechanics make house calls

Q: Idles and stalls again.

asked by on

why a car will start and idle a little bit,then quits.will start right back up,run a few then quit,there was a new starter just installed yesterday,there was an alternator put on about a month ago..

My car has 91498 miles.
My car has an automatic transmission.

Hi There, It 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

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. Idles and stalls again.

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: Help me please

If you have one cylinder that is low on compression and leaking oil into the cylinder then you have broken piston rings or a hole in the piston. The engine should have a cylinder pressure test to see if you...

Q: My car would start and turn off. I was told by dealership that I had a bad fuel pump driver module. When replaced it did not fix

I would suggest having the alternator checked to determine if it is receiving the proper amount of voltage from something called the voltage regulator. The voltage regulator regulates the charging voltage that the alternator produces, keeping it between 13.5 and...

Q: WOULD you get a po401code before a fulepump gaveout

Code P0401 relates to a faulty EGR valve and is unrelated to the fuel pump. It sounds like you may possibly have a stuck EGR valve. The EGR valve allows the flow of exhaust gases into the intake manifold in...

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.