How To Replace an Air Filter

How to Replace an Air Filter

What Is An Air Filter, and What Does It Do?

Your vehicle's internal combustion engine requires air, fuel, and spark in specific quantities to generate power. The necessary air is drawn from outside the vehicle and passes through the air filter before entering the engine. Outside air, however, is filled with potential engine-damaging contaminants, including grains of sand, leaves, dirt, pollen, even bird feathers. The air filter's job—much like that of the fuel and the oil filter—is to trap these harmful contaminants and prevent them from being sucked into the engine where they can cause damage.

When Should You Replace Your Air Filter?

An air filter is a maintenance item that needs to be replaced regularly. Ideally, that's every 12,000 miles or 12 months—more often if the vehicle is driven regularly in a dusty environment. As contaminants build up in the air filter's paper or cotton barrier, it becomes increasingly difficult for air to flow through, which, in turn, can cause significant engine performance problems.

Warning Signs Your Air Filter May Be Dirty

Your vehicle's performance problems may all stem from a dirty or clogged air filter. Here are several warning signs to look for:

  • Decreased engine power, throttle response, or acceleration
  • Poor gas mileage
  • Misfiring or rough-idling engine
  • Gasoline smell
  • Black smoke
  • Check Engine light illuminated
Vehicle System
Exhaust & Emissions
Skill Level

This is a good project for new DIYers

Time to Complete
15 minutes
  1. Purchase a new air filter that matches your vehicle make and model.

  2. Raise the hood and locate the air filter housing box. It's often a black plastic box with a hose coming out of it and is usually located toward the front of the engine compartment. On older vehicles equipped with a carburetor, the air filter will be round and located in a metal housing that fits over the carburetor.

  3. Determine how the cover on your vehicle's air filter housing box is removed. On most, there are two clamps, wing nuts, or screws holding it in place. Release and remove the cover.

  4. Remove the old filter, noting in which direction it was installed as this matters for air flow. Inspect the old filter for dirt and debris. If it appears clean and is relatively new, it probably doesn't need to be replaced. If it's clean enough, you should also be able to see light through the filter.

  5. Compare the old filter with the new one to ensure they match.

  6. Install the new filter in the same direction that the old filter was installed.

  7. Replace the filter box cover and secure it.

Last updated June 8, 2018