Changing an Air Filter
Before you start heaving luggage out of your car's side windows or imposing passenger weight restrictions to improve your vehicle's mileage, check the air filter. A dirty or clogged air filter can alter your vehicle's gas mileage by up to 10%.
An air filter serves as an engine's protection device against grit and grime―your car's Achilles' heel. An air filter that is blocked with debris essentially chokes your vehicle and restricts air intake.
Fortunately, changing an air filter usually takes under five minutes.
When to Change the Air Filter
An air filter should be replaced once a year, or every 15,000 miles. If you regularly travel on dirt roads, however, you will need to check your air filter every few months. You don't need a mechanic's eye to determine the air filter's condition. If you see dust build-up within the filter's accordion-like folds, change is needed. Or, for absolute certainty, shine a flashlight from the inside out. If the beam cannot penetrate the folds, you need to spring into air-filter-maintenance mode.
How to Change an Air Filter
To find your air filter, pop the hood and look for a black plastic casing―about the size of a bread loaf―fastened with clips or screws. If you're still unsure, consult your car's manual.
Open the clips. You can do this with your hands, or if you're intent on keeping the fingers grime-free, use a screwdriver.
If you drive an older car, you'll find the air filter above the engine, encased in a round black covering that looks like it could contain a pillbox hat. Unscrew the center wing nut to open.
Next, remove the filter and inspect it for dirt by bending back the paper ridges. If deemed filthy, go purchase a new one.
Insert the new filter and make sure the casing is tightly secured.
Not only is this fast, but cost efficient. Most quick lube shops charge up $20 to change an air filter. For a few minute's time, you can save yourself half the cost by self-installing.
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