Keeping Your Car in Shape
Keeping your engine tuned up can be one of the most effective things you can do for your gas mileage. The US Department of Energy says that repairing some problems that can be uncovered with a routine engine tune-up can improve your fuel economy by as much as 40 percent. And other fixes, such as putting the right grade of motor oil in your vehicle and keeping the right amount of pressure in your tires, don’t take much time.
So before you head out on your summer road trip, or even drive to the park for a picnic, take a moment to make sure your car is in good working order. It will be more than worth your time when you notice the savings.
Keep Your Engine Properly Tuned
Fixing a car that is noticeably out of tune or has failed an emissions test can improve its gas mileage by an average of 4 percent, though results vary based on the kind of repair and how well it is done.
Fixing a serious maintenance problem, such as a faulty oxygen sensor, can improve your mileage by as much as 40 percent.
|Fuel Economy Benefit:||4%|
|Equivalent Gasoline Savings:||$0.15/gallon|
Keep Tires Properly Inflated
You can improve your gas mileage by up to 3.3 percent by keeping your tires inflated to the proper pressure. Under-inflated tires can lower gas mileage by 0.3 percent for every 1 psi drop in pressure of all four tires. Properly inflated tires are safer and last longer.
The proper tire pressure for your vehicle is usually found on a sticker in the driver’s side door jamb or the glove box and in your owner’s manual. Do not use the maximum pressure printed on the tire’s sidewall.
|Fuel Economy Benefit:||Up to 3%|
|Equivalent Gasoline Savings:||Up to $0.12/gallon|
Use the Recommended Grade of Motor Oil
You can improve your gas mileage by 1–2 percent by using the manufacturer’s recommended grade of motor oil. For example, using 10W-30 motor oil in an engine designed to use 5W-30 can lower your gas mileage by 1–2 percent. Using 5W-30 in an engine designed for 5W-20 can lower your gas mileage by 1–1.5 percent. Also, look for motor oil that says “Energy Conserving” on the API performance symbol to be sure it contains friction-reducing additives.
|Fuel Economy Benefit:||1–2%|
|Equivalent Gasoline Savings:||$0.04–$0.08/gallon|
Replacing a Clogged Air Filter on Modern Cars Improves Performance but Not MPG
A new study shows that replacing a clogged air filter on cars with fuel-injected, computer-controlled gasoline engines does not improve fuel economy but it can improve acceleration time by around 6 to 11 percent. This kind of engine is prevalent on most gasoline cars manufactured from the early 1980s onward.
Tests suggest that replacing a clogged air filter on an older car with a carburated engine may improve fuel economy 2 to 6 percent under normal replacement conditions or up to 14 percent if the filter is so clogged that it significantly affects drivability.
The effect of a clogged air filter on diesel vehicles will be tested in the near future.
Note: All cost savings are based on a fuel price of $3.87/gallon.