Replacing your air filter is an important part of maintaining your car or truck. One can often check and replace one's air filter oneself.

A car running with a dirty air filter is like an athlete struggling with an asthma attack-it simply cannot breathe and perform efficiently. According to AAA, www.aaa.com, oxygen is essential for proper fuel combustion in the cylinders. If you notice reduced engine performance, particularly when operating at high speed, it may be an indication of a dirty air filter. A clogged filter will also reduce gas mileage and increase emissions.

You should inspect your air filter each and every time you change your oil. Be certain you can see a bright light through the filter at all points. If you cannot, you should replace the filter. Mildly dirty filters can sometimes be cleaned by tapping them on hard surfaces or blowing them with compressed air. Those living in particularly dusty regions will often need to replace their air filters more frequently than those who don't.
How to Change Your Air Filter

eHow.com reports one can change one's air filter in 5 simple steps:

1. Pop the hood and find the air-filter housing. It will be either square (on fuel-injected. engines) or round (on older carbureted engines) and about 12 inches (30 cm) in diameter
2. Use a Phillips screwdriver to remove the screws or clamps that hold on the top of the housing.
3. Take out the old air filter and clean any dirt and debris from the housing with a clean rag.
4. Put in the new air filter.
5. Screw or clamp the lid of the housing back on.