As colder temperatures creep upon us, whatever cold weather routines we have also start to kick in. Habits like layering our clothes, tossing extra blankets on the sofa, eating soup, and buying stuff online seem to make the season more tolerable. Another pattern? Warming up the car before hitting the road.

The joys of winter! Folk wisdom has taught us that when it’s cold out, you start your car and let it idle so the engine can warm up. The thinking is that driving on a cold engine will harm the life span of the car. Some folks let it sit for 20 to 30 minutes, and others just 5 or 10.

Many of us warm it up so that we don’t have to do our morning drives in a car feels like a meat freezer. Who likes to drive around like that when it’s 12 degrees outside on a dark morning? Not to mention, if your windshield is covered in frost, does it really make sense to skip the thawing?

Mechanics and auto experts are rebuffing the “warm your engine up first” stance, citing strides in auto engineering. According to Popular Mechanics, a combustion engine’s ability to work depends on a mix of compressed air and gas vapors. To power up, it has to be just the right mix, but cold conditions can inhibit gasoline from vaporizing as it should. To compensate, the system will inject more fuel.

In layman’s terms this means that when your car is outside idling in the cold rather than being driven, you’re risking a higher amount of unevaporated gas getting into the engine. This is potentially harmful to your drivetrain because the gasoline can wash away oil that’s needed to coat the engine. Therefore, for modern cars with fuel injector engines, there’s no need to warm and sit idle.

The extra fuel injected to overcompensate for the engine’s paltry vapors will also cause you to burn more gas. Burning of extra gas = money wasted and more carbon dioxide being pumped into the atmosphere. So with all this, what do the experts recommend?

Start your car, and let it warm for a just few seconds, giving the fluids and engine a chance to wake up. If you have to clear the windshield, do it! Get in and drive it “gently” (the opposite of Nascar-style) for the first few minutes to allow the engine time to warm up properly. Whatever you do, try not to let it idle for 15 to 30 minutes, especially if your car is in a garage or other closed space.

In older cars with carburetors, it is still necessary to let the car idle, as they don’t have the technology to regulate the fuel flow into the engine. Some of you may very well be rolling around in whips that have carburetors, so to you: keep that engine humming on those frigid winter mornings.

If you need to defrost, de-snow, deice, and otherwise thaw out your vehicle, by all means do so. There’s no reason to risk a ticket, an accident, or frosty body parts. Just pay extra attention to your car’s needs during the winter months when the cold hits. Which camp do you belong to – warm it up or not? How long do you let your car idle on cold mornings? Share in the comments!