MILEAGE MAINTENANCE
$3.00 GAS IS HERE
On average, the U.S. population of vehicles will get about 20 miles per gallon (includes passenger vehicles & light trucks). A 0.7 of a mile improvement represents only a 3.5% improvement but this would represent a yearly savings of $17 billion in fuel if the cost of a gallon of gas stays around $3.00. This very small improvement of 3.5% can be achieved through simple maintenance that often goes unperformed. It is simple items like spark plugs, filters and engine sensors that can yield these improvements.
Here is a list of services that can help realize this small but important gain:
Gas mileage can be improved by 1 to 2% by just using the manufacturer’s recommended grade of motor oil and changing it at recommended intervals. Using 10W30 oil in an engine designed to use 5W30, can lower fuel mileage 1 to 2%. Using 5W30 in an engine designed for 5W20 can lower mileage 1 to 1.5%. A 2% gain in fuel economy can mean a savings of $37.50 over a year’s time.
Replacing a clogged air filter can improve a vehicle’s fuel mileage by as much as 10%. Engines use up to 14,000 gallons of air for every gallon of gas. A restricted air filter will cause the engine to run rich. Having the air filter replaced can save an average of $202.50 a year.
Replacing worn spark plugs can result in a 3 to 4% increase in fuel economy. As spark plugs wear, the voltage required to fire that plug increases. Once the voltage required to fire the plug exceeds the voltage reserve a misfire occurs, this sometimes is so slight it may not be felt by the operator. Spark plug replacement could mean a savings of $75 to $90 over a year at the pumps.
Replacing a worn or defective oxygen sensor can result in a 15% gain in fuel economy. As an oxygen sensor ages, it becomes slower to respond and sends inaccurate readings resulting in improper fuel mixture signals to the injectors and a decrease in fuel mileage. Replacing the oxygen sensor can mean a fuel savings of $295 over a year.
Other engine sensors, like mass air flow or throttle position sensors, can impact fuel mileage between 10 to 25%. These repairs may seem like a lot at the time but when weighed against the savings of $202 to $450 at the pump over a year, the choice is clear.
A study shows that 17% of the vehicles on the roads have gas caps that are either damaged, loose or are missing altogether, causing 147 million gallons of gas to vaporize every year. This figures out to $436 million if gas prices stay around $3.00 for the next year. Replacing a broken or defective gas cap could improve fuel mileage by .5% in some cases.
Proper wheel alignment is critical for fuel-efficient driving. If a vehicle is driven 12,000 miles and the wheels toe is tilted inward by .34 of a degree out of specification, by the end of the year the tires have been dragged sideways for 68 miles. This not only wastes gas but shortens the life of the tires. Proper tire inflation is also critical for fuel efficiency and tread wear.