One of the easiest things you can do to your car to help bump up the fuel economy is replace a clogged air filter. Not only is a clogged air filter bad for fuel economy, it can also cause other problems for your car.
Since it was time to replace the air filter in the wife's 2004 Kia Sedona Minivan, I didn't want to have to buy several of them over the course of the vehicle's life. So I decided to go with a K&N drop-in replacement filter. Instead of throwing it away when it becomes clogged, you clean it and reuse it. Good for your car, good for the environment. Plus, since my car isn't as popular as a Honda Accord lets say, you don't have to worry about going to the auto parts store and finding they don't have the correct filter for your car.
I started out by laying out the air filter on the hood of the car. It comes pre-oiled so they pack it in a plastic bag with a K&N sticker warning mechanics not to throw the filter away because it has a million mile life. As you can see, the stock filter was pretty clogged up.
Installing the filter is pretty easy. The manufacturers make replacing air filters for the most part simple. Some use screws to hold the filter in the air box, others use a spring latch to hold it down. The only tool I needed to install the filter was a phillips head screwdriver.
I undid the screws, and the air box just popped open. You don't have to remove the air box, just open it enough to let the filter (which as you see above is only about 1" thick, pop up and out). At this point, I've spent more time taking pictures than I have actually working on the car.
After pulling out the old one, I took a damp rag and wiped the inside of the air box to get any residue dust out. Just a precaution, since the filter just grabs most of it any way, but any dust you catch on your towel is less dust you have to clean out later. Next I put in the new filter, and closed it back up.
Last but not least, since I was attaching the K&N sticker, I wiped down the top of the airbox and attached the sticker. Mission accomplished, total elapsed time was about 15 minutes, with about 5 of those minutes spent taking or posing for pictures.