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Q: What can cause intermittent cold starting fault?

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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.

A: This may be related to a cold start enrichm...

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.

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