Clean air filter is key to engine performance

Checking you air filter on a regular basis is key to engine performance. all vehicles have one and it is easy to check and or replace.
A clogged air filter affects your car's performance on a number of levels. It robs your car of power, something you need every ounce of when you're navigating a freeway on-ramp. Perhaps more important is the effect a clogged air filter has on your gas mileage. It takes 10 minutes and usually costs less than $20. These easy steps will get you there and back in no time flat.
Difficulty: Easy
Time Required: 10 minutes
Here's How:

1. Locate and Open the Filter Housing
With your hood open and safely propped, locate the air filter housing. On any car made in the last 20 years or so, it'll be in a black plastic case with metal clips on the sides. You'll also see a black tube going into the plastic case on most cars. Flip the little metal clips downward. If they are tight, slide a flat-head screwdriver in between the clip and the case from the top, and pop it off. Some housings will also have a nut holding them from the top.
2. Squirrel Your Nuts
If you removed nuts from the top of your filter housing, be sure to put them in a safe secure location. You don't want to lose these! In the vehicle used in our example, the top of the filter housing comes off, so we put them in the housing top where they couldn't roll away. You can even stick them in your pocket. Whatever you do, put them someplace safe.
3. Remove the Old Filter
Your filter (round or rectangular) will be made of lots of folded paper surrounded by rubber. Before you remove the dirty filter, take a moment to note how it sits in the housing so you can be sure to put the new one in correctly. Carefully pull it out, being sure that nothing falls into the bottom of the box. I've seen sticks, trash and some really big bugs caught in the filter. If it looks anything like the filter in the above photo, you know you're doing the right thing.
4. Put the New Filter in Place
Put the new, clean filter in place, being sure to put it in the same configuration as the one you removed (as in which side is up, etc.). Don't worry about making a mistake here, if you have the filter in upside down you won't be able to get the top closed. Also be sure to press the rubber gasket of the filter all the way into its groove in the housing. If you find the cover hard to get back on, re-check this as it's often the culprit.
5. Empowerment!
That's it! You just saved money on gas, and saved a nice bit of cash by installing the air filter yourself.