Mileage Myths costing drivers

As gas prices rise, people seeking to improve their milage with old wives' tales are often making matters worse:

In the quest to squeeze as much mileage out of their gas budgets as possible, motorists are exploring all the angles, gleaned from friends, family and even the Internet. Some work; others are urban myths.

Turning off the air conditioning and opening the windows, for example, actually lessens fuel economy because air going through the windows adds drag to the car.

Myung is not alone in thinking gas prices go up on weekends, but experts say he's wrong.

"That's a bit of an old wives' tale, a myth," said Tom Kloza, chief oil analyst for the Oil Price Information Service. "Wholesale prices change every day, with the exception of Sunday. The biggest price moves tend to take place on the wholesale markets on Wednesdays these days."

But there does appear to be truth to the theory that stations near freeways charge more.

"There's substantial premiums you pay if you buy gas near a freeway," said Michael Shames, executive director of the Utility Consumers' Action Network, a San Diego group that has tracked regional gasoline prices. "It's simply a function of gas stations' taking advantage of the convenience factor. They may also pay higher rents, though."

How about driving behind a big rig? That also can improve fuel economy.

"It's the same theory that Lance Armstrong exploits whenever he's riding in the Tour de France," Shames said. "He's taking advantage of the draft created by other riders to reduce the amount of effort he has to make."

However, experts don't recommend the technique for motorists because of the dangers of being in the trucker's blind spot.