Engine Air Filter: Your Subaru’s engine requires clean air to operate. The engine air filter is what keeps all dirt, dust and debris from entering your engine, while allowing the appropriate amount of air to enter the engine. While the lifespan of your air filter varies depending on what kind of conditions you drive in, it is recommended that you have it replaced every 30,000 miles or so. Cabin Air Filter: The cabin air filter is what filters the air that comes through your heating and cooling ventilation systems so that you can safely breathe in clean air. This filter gets clogged over time, and should be replaced periodically.
How do I know if I need new air filters?
If you see a decrease in gas mileage, your engine starts making abnormal sounds, or you see black smoke coming out of your exhaust, it may be time for a new engine air filter
If your air conditioning or heating system’s airflow becomes less-strong or you detect a strange smell when the system is on, you may need a new cabin air filter.