How to stop guzzling gas

The higher-priced fuel may have more of this or that additive than the regular grade, but not enough to make a difference in your car's performance. So it's a waste of money to buy premium gas on every third fill-up on the theory that the additives will clean the car's fuel system.

Follow the recommended service schedule listed in the owner's manual and change oil, engine coolant, filters and spark plugs at recommended intervals.

And keep the engine tuned. This will reduce emissions and can save about 5 percent on gas. Check and replace the air filter regularly because a fouled filter can reduce your gas mileage by as much as 10 percent, according to the Department of Energy.

Also use the recommended grade of engine oil. Using heavy oil in an engine designed for light oil can reduce mileage by 1 percent to 2 percent. And if possible, use oil with friction-reducing additives.

Buy a tire gauge and use it once a week to be sure your tires are properly inflated. The Department of Energy says under-inflated tires can lower gas mileage by as much as 0.4 percent for every one-psi drop in pressure in all four tires. Properly inflated tires also will improve handling and last longer.

Pump Busters 2006 Small cars Family sedans Upscale sedans Luxury sedans Large sedans Hatchbacks Convertibles Sports/sporty cars Wagons Pickups Sport utility vehicles Minivans Source: Forbes.com

It's easy to make several short trips each day, but with a little planning, it's possible to combine trips and save gas.

If you drive to work, see if you can go in a little early or late to avoid the morning and evening crush. This means spending less time in bumper-to-bumper traffic and saving gas. At the same time, try to avoid long waits for left turns. UPS, which worries a lot about saving fuel, finds that constant waits for opposing traffic can eat up gas.

When on vacation, remember that anything you put on the roof adds weight and increases wind resistance. The Department of Energy says a loaded roof rack can cut fuel economy by about 5 percent. Put as much stuff as possible inside your car. And be sure to remove the rack when not in use because, even when empty, it increases aerodynamic drag, chewing into your mpg.

Heavy use of your air conditioner can increase gas consumption 10 percent to 20 percent. Roll down the windows instead. Amazing, eh?

You don't need to shove a tank around town. When prices were low, few cared that behemoths gobbled gas. Assuming a price of $2.20 per gallon and driving 15,000 miles per year, the difference in fuel cost between a car that gets 20 mpg and one that gets 30 mpg is $550 annually. If your car doesn't match the way you use it, consider getting another one if the replacement cost pencils out.

Honda Motor, Toyota Motor, General Motors, Ford Motor and DaimlerChrysler all offer vehicles that get good gas mileage. So shop around.

Finally, "I check under my hood weekly, and I recommend everybody do the same," Cox says.

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