http://www.alternativefuelstips.com

A clean air filter is the key to good fuel economy. A dirty air filter restricts the flow of air into the engine, which harms performance and economy. Air filters are easy to check and change; remove the filter and hold it up to the sun. If you can't see light coming through it, you need a new one. Use K&N filters which is cleaned rather than changed; they are much less restrictive (better air flow) than throw-away paper filters, plus they're better for the environment. The safest solution in order to save fuel is to go for a gas additive as a fuel saver because its effectiveness is guaranteed.

http://www.alternativefuelstips.com