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DCL

An improperly tightened gas cap might be low on your list of vehicular priorities, but the 17 percent of autos on the road that have gas caps that are loose, defective, or missing altogether cause 147 million gallons of gas to vaporize into the air every year, according to the Car Care Council.

Keep your fuel from going MIA-make sure your gas cap is screwed on tight every time you're done filling 'er up.

Difficulty level: Easy