Clean Air for Better Mileage

Gas prices are projected to top $5 per gallon this year. With that thought in mind, plenty of Americans are trying to maximize the distance they can travel per gallon of gas in their cars. Many suggestions for ensuring you get the most out of your fuel include making sure your tires are properly inflated and using good quality gasoline.

One area that often gets overlooked in spite of its ability to greatly affect your fuel mileage is your car's air filter. This essential part of your car's induction system plays a vital role in protecting your engine from harmful contaminants. The filter is designed to keep dirt, dust, grime, and other pollutants from entering into your engine's intake. If introduced inside your engine, these particles can mix with the air/fuel mixture and really gunk up the works. Buildup inside dirty engines can cause fuel injectors and valves to function improperly as well as disrupt the flow of air through your motor, hampering its efficiency and decreasing your fuel mileage. Dirty air can also cause fuel to burn improperly and result in reduced power and performance.

It's easy to see the importance of keeping your engine's internals clean and efficient. You can help to ensure that this happens by always having a clean air filter working inside your air box. If you do have a dirty or clogged air filter, replacement is relatively simple and quick. Follow these steps to check and if necessary replace your air filter:

1. Locate your vehicle's air box. It will be under the hood of your car, connected to the intake tubing. Some vehicles have it clearly labeled while others may not.

The air box is the rectangle shaped plastic box on the right side of this photo.

2. Locate and release the clips securing the lid or cover to the airbox. Different vehicles have different ways of making sure the airbox stays closed, so look for something like the clips in the photo. Your car may have fewer or more than the two in this application.

This airbox is secured by two metal clips seen on the right in this photo.

To release the clips, simply use your thumb to pop them off.

3. Remove the airbox cover to reveal your air filter. Use caution as some airboxes may have wires and sensors connected to the cover. Move the cover out of the way gently to access the air filter.

 4. Remove the air filter from the airbox housing. Most filters just sit on a rim inside the airbox. Lift one edge to loosen the filter and remove it form the airbox.

5. Inspect your air filter for trash and dirt particles lodged in between the pleats. A lightly used air filter will have some dust and dirt trapped in it, but may still be able to function fine. A gentle shake can dislodge any loose larger sized particles and the filter can be reinstalled. If your air filter has an excessive amount of trash and dirt trapped inside however,  it may be time to replace it altogether. Look in your vehicles owner's manual and visit a local auto parts store to find what filter you need for your vehicle.

This air filter is in need of replacement. (source: knfilters.com)

Some air filters have the model number printed on the side.

6. With the filter out, check the inside of the airbox for loose dust and dirt. If there is any dirt sitting in the bottom of the airbox, clean it out with a damp cloth.You may encounter larger stuff like leaves or dead bugs. Make sure to get those out of there also as they can easily block air flow.

This airbox is mostly clean and ready for a new filter.

7. With your clean or new replacement air filter, install it into the airbox the same way it was removed. Be sure to align it properly so the airbox cover can form a good seal.

Most filters will only fit in the air box one way. Make sure the filter sits properly in the airbox before replacing the cover.

8. Align the tabs on the airbox with the tab slots on the cover and place the cover back on the airbox. Improper alignment will not allow the cover to close properly.

This airbox has two tabs seen here on the left.

The tab slots on the cover should line up with the tabs on the airbox.

Proper alignment should look like this.

9. With the cover back in place, snap the clips back that hold down the cover.

A properly reinstalled airbox cover with clips in place.

With the cover back in place you are done. The clean air filter will better protect your engine and ensure that you are getting optimal airflow. Better airflow leads to better fuel mileage.

Replacing your air filter is part of the scheduled maintenance for your vehicle and should be performed in accordance with your manual's listed intervals. If you frequently operate your vehicle in excessively dusty environments or idle for extended periods of time, it may be necessary to replace your filter sooner than called for in the maintenance schedule.