Avoid luxury gas
Premium fuel costs about 20 cents a gallon more than regular. If your car doesn't need premium grade fuel, don't buy it. Check your owner's manual. If the manufacturer does not require high-octane fuel, your car will run just as well on the least expensive gas. Avoid mid-grade fuel, your engine either needs premium or regular.
Shop aggressively
Since prices change overnight, the gas station that offered the best deal last time you filled up may be the most expensive the next time your tank is empty. While it doesn't make sense to drive out of your way to save a few cents per gallon, you can save money by simply paying attention to the posted prices at the gas stations you pass every day.
Routine maintenance PAYS OFF
A dirty air filter and under-inflated tires could be costing you up to 10 percent more at the gas pump. For every pound of pressure your tires are under-inflated, you could be losing up to 2 percent of your gas mileage.