WASHINGTON - Your car's gas mileage may be worse than you think.
When cold weather hits, gasoline powered cars use more gas when they start and as they're warming up and batteries are under more stress.
That means in 20-degree weather, gas-powered cars are 12 percent worse on fuel economy than those same cars are at 77 degrees, according to research from the Oak Ridge National Laboratory.
The lab found hybrid cars are even worse with fuel economy dropping 34 percent.
In the winter, make sure your tires are inflated to the proper pressure, remove items like roof racks that can reduce aerodynamics and try to find a warm place to park your car, USA Today recommends.
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