Engines need the proper mixture of air and fuel to run right. The air filter is designed to protect the engine from contaminants, while also promoting airflow. Over time, however, the air filter accumulates dirt and debris that prevent air from entering the engine. This causes the engine to work harder and reduces engine performance.
A clean air filter restores engine power and efficiency by allowing fresh air to enter the engine. To protect your engine and keep it running at peak performance, the air filter should be changed on a regular basis. Generally, this is every 15,000 to 30,000 miles.