Q: Car cutting out when slowing down

asked by on

Recently bought my car and within the first few days I had the MAF and secondary air pump replaced. My car has an intermittent fault we're it cuts out when I slow down to under 20mph when it's warm. Slowing down for bends, traffic or traffic lights. It could be potentially very dangerous. No other faults are coming up on the diagnostics. Any help will be much appreciated. Thanks in advance.

My car has 95000 miles.
My car has an automatic transmission.

This may be related to 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. 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. This is all controlled by the idle air control valve. When the engine RPM drops below the normal range of 750-800 RPM (for most cars), 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. Car cutting out when slowing down

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: When stopped waiting at a stop light, the engine RPMs will drop a bit and it sometimes stalls out.

This is a common sign of 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...

Q: My car is overheating due to water pump and the nearest Autozone is 30 miles away. Would it be okay to drive? 2001 Mercedes CLK320

Hello - if your car is already overheating, NO - driving it any further is not a good idea. Newer engines with aluminum cylinder heads, and aluminum blocks, are ever more sensitive to overheating. Blown head gaskets or worse can...

Q: Car misfire at idle.. changed plugs..coils..air fliter. gas smell and a miss sometimes. Any ideal was happening?

With the recent repairs made, chances are your issue is related to the fuel-system or a stubborn sensor that's on its way out. When was the last time you changed your fuel filter? The fuel injectors can also cause misfiring...

Related articles

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 to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
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.