Changing Your Air Filter
The car's air filter keeps impurities in the air from damaging internal engine components. Not only will replacing a dirty air filter improve fuel economy, it will protect the engine. Clogged filters can cause up to a 10 percent increase in fuel consumption. Keeping the filter clean can lower your air conditioner's energy consumption by 5%–15%. So don’t risk it!

Keep Your Engine Tuned
Studies have shown that, depending on a car's condition, a poorly tuned engine can increase fuel consumption by as much as 10-20 percent.

Changing Your Oil
Changing the oil regularly will increase the life of the car's engine. Clean oil reduces wear caused by friction between moving parts and it removes harmful dirt and grit from the engine. Some oils contain additives that reduce friction and may increase a vehicle's fuel economy by three percent or more.

Check The Air Pressure in Your Tires
Radial tires can be under inflated yet still look normal, so check the tires with a gauge. On average, tires lose about one psi per month and one psi for every 10-degree drop in temperature. Under inflated tires cause fuel consumption to increase by as much as six percent, cause the tires to wear quicker and can make it difficult to handle the vehicle.

*Figures based on average overall fuel efficiency of 20 mpg and annual mileage of 18,000 per year.