A Guide to Your Car’s Cabin Air Filter

Breathe easy with these tips on limiting airborne pollutants in your car.


What do exhaust fumes, pollen and road dust have in common? They’re all pollutants that can contaminate the air in your car. What’s worse, airborne pollutants can cause sneezing, blurry vision, runny nose and headaches, all of which can distract you while you’re driving. Fortunately, your car has a defense against dirty air—the cabin air filter.

What does a car’s cabin air filter do?

When your car windows are closed, outside air still comes into the car through vents. But before it enters, the air passes through the cabin air filter to remove pollutants. If you or your passengers have allergies, asthma or other respiratory issues, keeping your cabin air filter functioning properly is especially important.

How effective are cabin air filters?

The types and sizes of contaminants a cabin air filter can trap vary with the specific filter design. Standard filters are typically extremely efficient at trapping certain particulates, but they won’t remove fine particles like bacteria or smoke. And while High Efficiency Particulate Air (HEPA) filters can trap pollen, soot, mold spores and germs down to 0.3 microns, they’re not able to protect against coronavirus particles, which measure between .06 and .14 microns.

Does the air filter impact a car’s scent?

If your car’s interior has an unpleasant smell, turn on the cabin fan and find out if the odor is coming from the car’s vents. If it is, the culprit could be the cabin air filter. Moisture can condense on it and develop a sour or mildewy smell—and result in the need to replace the filter.


How easy is it to inspect a cabin air filter?

That all depends on the location of the filter, which is determined by the model of car you drive. Often the air filter is located behind the car’s glove compartment and is reachable by unfastening the glove compartment from the dashboard. Other possible locations—such as further under the dashboard or under the hood near the base of the windshield—may be harder to get to. If your cabin air filter can be reached easily, your owner’s manual will show its location and how to remove it for inspection or replacement. Remember that AAA Members save 10% and earn NAPA Rewards points on most auto parts and accessories at NAPA.

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When should your cabin air filter be replaced?

Your owner’s manual will list the mileage at which the cabin air filter needs to be replaced, but mileage isn’t the only factor that determines an air filter’s lifespan. Driving off-road, in dusty conditions or in places with poor air quality can clog the filter and cause airflow to decrease. If that happens, it’s time to replace the filter.

Is replacing an air filter a DIY job?

If you can easily reach your cabin air filter, replacing it is a job that can be done in about 15 minutes with a few tools. If it’s behind the glove compartment, replacing it is going to take a little longer and will require removing the fasteners that hold the glove compartment (and/or interior trim panels) in place. If you need help replacing your filter, check with your local auto repair shop.

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