Car Stalls in Cold Weather

If your car starts fine in warm weather but stalls in the cold, the engine isn't getting the right fuel or air for cold conditions.

Cold-weather stalling is usually tied to the cold-start enrichment system. The engine computer uses the coolant temperature sensor to determine how much extra fuel to inject when the engine is cold. If that sensor is inaccurate, or if the idle air control valve is sluggish at low temperatures, the engine may start but stall shortly after because it can't maintain the higher idle speed needed when cold. Fuel injectors that are partially clogged may work adequately when warm but fail to deliver enough fuel for cold conditions.

Moisture in the fuel system can also cause cold-weather stalling. Water condensation in the gas tank or fuel lines can freeze and block fuel flow. Using fuel with ethanol content helps absorb small amounts of moisture, but significant water contamination requires draining. Cold temperatures also thicken engine oil, which adds more resistance than the engine can overcome at an unstable idle speed.

Cold-weather stalling in Jacksonville is usually limited to a few weeks in winter, but it's miserable when it happens. Ez Mobile Mechanic comes to your location and diagnoses the issue — we're a mobile mechanic in Jacksonville who handles cold-start problems on site. No tow truck, no shop drop-off. Call (904) 788-7272.