Q: Q: Car stalling

asked by on

Hi My car will sometimes stall when shifting from reverse to drive. Sometimes needs longer than normal cranking time to start. The ideal rpm seem to fluxuate when the engine gets warm. The spark plugs and wires are new and the mass air flow sensor has been cleaned. A code reader shows no unusual codes. Please help.

My car has 62000 miles.
My car has an automatic transmission.

You may have 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 at idle. Since this valve is controlled by the vehicle’s computer, it 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 with the help of the idle air control valve. 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 repair your idle air control valve.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Q: Car stalling

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: Spare key starts vehicle but shuts off after like 10 seconds.

Hello and thank you for contacting YourMechanic. Remove the negative battery cable to the battery and leave it off for about 2 minutes. This will cause the computer to reset. Then hook up the battery cable and start up the...

Q: When i am at a stop light or stop sign. Randomly my car will lose power and go dead.

Poor idle can often be caused by vacuum leaks. Any air that gets into the engine without going through the proper channels will lean out the system and cause problems like you are having. Look under the hood for any...

Q: car shaking when idle, bad exhaust, low engine temperature

If the muffler is loud because it is leaking exhaust gases (as opposed to just having broken internal baffles) the car is not safe to drive because exhaust gases contain carbon monoxide. The cost to repair the loud exhaust depends...

Related articles

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...
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...
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.