Get Better Gas Mileage and Fuel Economy with These DIY Car Care Tips, Why spend more at the gas pump when you can easily spend less? The team at The Family Handyman shares this list of DIY tricks for a noticeable difference in your fuel costs. The savings are based on driving 20,000 miles per year, in a car that gets 20 mpg, with gasoline priced at $3.75 a gallon.
Surveys show that 60 percent of the vehicles on the road have tires that are underinflated by at least 30 percent. That's at least 9 psi below the manufacturer's recommended pressure. That can cost you almost 7 percent in wasted fuel ($245 per year, or 24¢ per gallon). Plus, low air pressure causes premature tire wear, and that can cost almost $300 over the life of the tires. For best results, check your tire's air pressure with a digital pressure gauge (about $10 at any auto parts store) and fill to the recommended pressure shown on the decal inside the driver's door or on the driver's door pillar.
If your 100,000-mile spark plugs have 80,000 miles on them, they're 80 percent worn. Misfires and incomplete combustion occur more frequently during that last 20,000 miles, costing you almost $562.50 in wasted fuel. You have to replace your spark plugs anyway, so do it early and pocket the savings. Even if you have to replace the plugs one extra time over the life of your car, you'll still come out way ahead. And don't automatically assume your plugs are good for 100,000 miles. Many four-cylinder engines require new spark plugs at either 30,000 or 60,000-mile intervals.
Your engine sucks in 14 million gallons of air through the filter every year. On older vehicles (pre-1999) a dirty air filter increases fuel usage by almost 10 percent ($350 per year, or 35¢ per gallon). On newer vehicles, the computer is smart enough to detect the lower airflow, and it cuts back on fuel. So your engine will lack power and pick-up. Check the filter when you change your oil and replace it at least once a year, or more if you drive in dirty, dusty conditions.