Expert: Mike Evans - 9/24/2010

Question
Is it better to let your car idle during winter or to turn it off when stopped? What affect would turning it off and on have on the starter of a car?

Answer
    Current wisdom says: no idling.  Idling uses fuel, creates emissions, and is harder on the engine (especially the crankshaft).  However, every time you use the starter is one less time it will work over its lifespan.  The way I see it: if it is below freezing and the stoppage will be brief, let it idle.  If it is in the forties, or the car will be stopped for a long period, then shut it off and restart it when the time comes.  Of course, if you are having a hard time starting in cold weather then you might want to let it idle rather than get stranded somewhere.  Also, idling cars are more likely to get stolen.