Love it or hate it, winter robs your ride of fuel efficiency

After winter snow, clear your vehicle s front air intake to ensure that the engine runs efficiently. Photo by Metro Creative Graphics
After winter snow, clear your vehicle s front air intake to ensure that the engine runs efficiently. Photo by Metro Creative Graphics

It’s hard to hate winter weather during the holiday season, but the reality is that once the new year dawns, and Old Man Winter tightens his icy grip, it’s going to cost you more to drive every day.

The U.S. Department of Energy says your vehicle’s fuel economy will drop 12 percent on a short drive across town when it’s 20 degrees or colder, compared to the same trip taken when it’s 77 degrees. And if the trip is exceptionally short, say 3 or 4 miles, fuel economy drops as much as 22 percent. If you have a gas-electric hybrid, it’s even worse, with fuel efficiency declining by up to 34 percent. That’s because lower speeds are controlled by electric motors, so it takes longer for the gas engine to warm up.

So why does this happen?

As the mercury tumbles, gasoline thickens and air becomes denser. This causes a less-than-optimal fuel-air mixture, and your car ends up consuming more gasoline until the engine and its fluids warm up.

“Well,” you say, “I have a heated garage.”

OK, it probably takes your car less time to warm up. But winter blends of gasoline have slightly less power than summer blends, so you’ll still guzzle more gas to perform as efficiently as you will six months from now. And if the fuel doesn’t get you, the air will. Since colder air is denser, it not only increases aerodynamic drag on your vehicle, it also lowers your vehicle’s tire pressure. As tires become under-inflated, rolling resistance increases, which in turn requires your car or truck to use more power to overcome it.

And, once it snows again, you have another culprit sabotaging fuel efficiency since snow adds weight. And more weight means more fuel needed to overcome it. So completely clean snow and ice off your car, truck or van. Also, clear your vehicle’s front air intake to ensure that the engine runs efficiently. Finally, if your car has four-wheel drive, and you don’t have to use it, don’t. Engaging four-wheel drive devours more fuel.

Of course, there are other things you can do to ensure your car runs efficiently in cold weather.

While cold weather might tempt you to warm you car by letting it idle, auto manufacturers suggest doing this for no more than 30 seconds. Why? First of all, the engine will warm up faster when it’s being driven. Secondly, idling returns a fuel economy rating of zero mpg. However, this doesn’t apply to a plug-in hybrid or electric vehicle. On those vehicles, preheating the cabin while they’re plugged into a charger can extend the vehicle’s range.

There are also the obvious ways to lighten the load, and save fuel, such as removing any exterior accessories that you’re not using, such as bike racks. They merely increase wind resistance.

Finally, it’s always a good idea to combining trips, especially in the winter. Doing this ensures that you’re not driving with a cold engine. And, although this seems obvious, park your vehicle in a warm garage if possible, or in a sunny spot. This helps increase the initial temperature of the engine and cabin.

You don’t have to like winter, but you have to love beating old man winter’s ice cold grip on your wallet.