Even though it’s cold outside, your engine can still overheat. Engine cooling systems are sometimes more susceptible to sudden failure during winter months. Colder ambient temperatures and sudden temperature changes adversely affect seals, hose connections and plastic parts. Equally susceptible are thermostats that can stick and cause intermittent overheat situations (see past tech tips for additional thermostat information).

If you notice a small leak under your car or a low coolant level indicator, do not hesitate to have it checked out. Failure to rectify a seemingly insignificant coolant loss can lead to costly repair.

Never drive your BMW in an overheated condition. Driving with the temperature gauge in the red for even two minutes will compromise your engine head gasket. Driving a further distance will severely damage the engine.

For more info about cooling systems, read Mike’s article on plastic embrittlement.