A dirty air filter reduces your fuel efficiency and increases air pollution. Check the air filter at every oil change. Replace the filter when it's dirty or according to the schedule in your vehicle owner's manual. A clogged fuel filter can cause engine performance to drop and may lead to expensive repairs. Replace it if it's dirty or every 15,000 miles.
Proper inflation decreases rolling resistance.
By using the proper amount of air pressure and rotating the tires frequently, you'll increase your mileage and reduce the amount of wear on your tires. See your vehicle owner's manual for the recommended tire pressure. Belts and Hoses. Each month, inspect your fan belts and hoses to make sure they're not ragged or leaking. If so, replace them.