Winter doesn’t just mean that you need to bundle up. It means we need to pay special attention to items that can be negatively impacted by cool, dry air. Everything from your water pipes in your home to the family car needs considerations during these times. Many people have operated under the assumption that letting their cars idle before taking off is better for the engine than driving away immediately after turning on a cold engine. But this is actually incorrect.

To understand why it’s not smart to let your car idle in winter, you need to understand car engines. Cars once used carburated engines but now rely on internal combustion engines, instead. Your car’s combustion engine relies on pistons to compress air and fuel in a cylinder. This, in turn, creates a tiny explosion that starts the engine.

A cold engine can struggle to ignite gas because the fuel doesn’t evaporate as easily. Some engines have sensors that compensate for this by pumping more gas into the mixture during winter. When the temperature of your engine rises, the sensor stops pumping extra fuel into the mix.

But if that gas gets into the cylinder walls when your car idles, it can strip away the oil that your engine needs to remain lubricated. Not only that, but you’re using extra gas when you let your car idle during the colder months.

Although your car might feel warmer inside once you let it idle, idling does little for the actual engine. So what’s the best way to warm your engine? Drive. As soon as the sensors determine that your engine is warm enough, that fuel mixture will go back to the standard ratio. Just make sure to drive cautiously as your engine warms. Gunning it right away will strain your engine.

Some people still prefer to let their engines warm up as they do things like clear snow and ice from their vehicles, but you don’t need to do more than that. Before you turn your engine on, however, make sure to make some noise by kicking your door or honking the horn to dislodge any animals that might have taken refuge from the elements on your engine or in your wheel well before you start your engine.