Skip the auto shop - Our mechanics make house calls

Q: What can cause intermittent cold starting fault?

asked by on

When starting my car from cold the car starts but unless I press down on the accelerator immediately the car will rev and then cut out. This only happens when starting cold but if it does not start it then takes several turns for it to start properly and white smoke comes out of the drivers side of the bonnet

My car has 71000 miles.
My car has a manual transmission.

This may be related to a cold start enrichment problem which is generally controlled by the coolant temperature sensor. This sensor relays the temperature of the engine coolant to the computer which then makes fuel adjustments based upon the air temperature and coolant temperature. Generally, when an engine is cold, it will need more fuel than normal in order to start and run until the engine temperature reaches the normal operating temperature.

This may also be related to a dirty or failing idle air control valve. The idle air control valve reads 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 the engine RPM drops below the normal range of 750-800 RPM (for most cars), this may indicate a dirty or faulty idle air control valve.

I would recommend having an expert from YourMechanic come to your location to diagnose the starting issue and repair your idle air control valve as necessary.

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. What can cause intermittent cold starting fault?

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: fuse box diagram makes no sense. I'm looking for the left tail light fuse which says it's F48, which doesn't exist in my fuse box.

All your exterior are controlled by the lighting control module and if you have problems with only one light then your will need to have the lighting module scanned for problems to see if it needs wire repair or a...

Q: The ignition coil problem

Your vehicle's engine is equipped with 4 ignition coils, one for each cylinder. Unfortunately, these ignition coils are a common failure point with the VW 1.8L engine. There is always a chance that when one fails, another one may fail...

Q: Alternator not charging

Hi There, It sounds like you may have a faulty voltage regulator. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result 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...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...