Answer: Air filters play a vital role in allowing your engine to run efficiently while keeping it clean. Engines require a free flow of clean air to operate. Outside air goes through the air filter, into the intake manifold, and mixes with your vehicle’s gas to power your engine. Engines require exact ratios of air and gas for engines to run as efficiently as possible; so, it is important to have a clean air filter. There are many contaminants that can get into your engine, such as dust, dirt, salt, tiny rocks, bugs, etc. Air filters have to stop these contaminants before they damage your engine by clogging passageways or damaging pistons and other internal engine parts.