"The more maintenance you do, the better it'll run," explains Ron Stinson of Shroyer's Auto Body Shop.

Anything that's not in working order creates drag on your car, he says, and that reduces mileage. Check tire pressure and your air filter in particular, and use an additive to clean your fuel injector once a month.

When you're not driving, park your car in the warmest place you can find. Cold wind thickens the oil and makes it harder to start. Those hard starts use more gas.

He says speed uses more gas than miles traveled, so a steady pace will save you gas.

"If you are at home, and you're running in for just a second, leave it running," he says. That uses less gas than restarting.

Stinson says the combination will make a difference, but the sure fire saver, "Plan ahead, plan where you're going, take the route you thinks easiest."