For many Minnesotans letting the car warm up fully before driving off is a ritual they have been following forever. But is it a necessary? There are two reasons drivers typically let their car warm up before driving. First, it’s more comfortable to drive in car that’s warm, especially if you have remote start and don’t have to go outside to a cold car. Second, there’s the belief that driving off too soon in cold weather can harm the engine.
In the past, say 35 or more years or more ago, it would have made sense to let a car warm up before driving, but the reality is there’s no need to let modern cars warm up before driving. With today’s fuel injection systems, more advanced motor oil, and computer engine management, you can safely drive your car about 30 seconds after starting the engine. However, until the engine has reached normal operating temperature it’s best to accelerate gently.
By driving your car within a minute of starting in cold weather you’ll avoid wasting gas, create less pollution and enjoy an interior that warms up faster, since heaters begin working sooner when a car is accelerating than they do while idling. One exception for letting your car warm up is when the vehicle is covered in snow or ice. It’s sometimes necessary to run the vehicle when the defroster cannot effectively melt window ice and visibility is compromised.
If you do let your car idle for more than a few minutes during cold weather, keep in mind that may cities have laws against letting cars idle while unoccupied. Idling cars with the keys inside are an invitation to car thieves and cause excessive air pollution.
So, unless you’re driving an older car without fuel injection, or need to defrost ice from the windows, it’s best to start driving about 30 seconds after starting your car.