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Changing Your Air Filter

Clearing the air for better performance

Think of your engine as a giant air pump. It takes in air, mixes the air with fuel and ignites this mixture in order to produce the power to get your vehicle down the road. Over the course of even a minute, your engine takes in a massive volume of air—and all of it enters through the air filter. A small 2-liter engine can breathe nearly 3,000 liters of air per minute at comfortable cruising speeds. Imagine 1,500 empty 2-liter bottles of soda, and you get the idea.

Air Apparent

Along with all that air comes everything floating or flying around in it. Over time the air filter can become clogged with dirt, grime, bugs and debris, causing a loss in both performance and mileage. Replacing your air filter on a regular basis is easy, and can save you a few bucks over time. Not only will you keep incoming air clean to help prevent engine wear, you'll also help keep your engine breathing at maximum efficiency.

The paper or filter media in the air filter collects all manner of things over the course of its service life. Once too much gunk gets into the pores of the filter, it can't breath deep anymore. At this point your engine can't take in the proper amount of air to mix with fuel, and can run rich—too much fuel, not enough air. Rough running, poor mileage and lousy performance can result from a clogged air filter.

Change of Scene

Knowing when to change your air filter is as easy as opening your owner's manual. Most service intervals run in the 9-12,000 mile range. If your manual is missing then inspect your air filter every time you change your oil, and replace it as needed. Keep in mind that intervals shorten for severe duty. If you live where there is a great deal of dust, stop-and-go traffic, or airborne contaminants, air filter service intervals should be more frequent.

To change the air filter open up the hood and find what looks like a box with a tube or snorkel connected to it. The air filter is inside this air box. Older carbureted vehicles have a circular canister on top of the engine that houses the air filter. If you see neither of these assemblies it's best to consult the owner's or service manual for location and replacement procedures. Otherwise, replace the old air filter with the new one, and that's it.