Air filters reside in the air-intake system, and they're there to catch dirt and other particles before they can damage internal engine parts. Engine air filters are usually made of paper, although some are made of cotton or other materials, and they should be replaced according to your manufacturer's maintenance schedule. Usually your mechanic will check the air filter whenever you get your oil changed, so get a good look to see how much dirt it has accumulated.
Most modern cars also have a cabin air filter that catches dirt, debris and some allergens in the air that goes through the heating, ventilation and air-conditioning systems. Cabin air filters also need periodic changing, sometimes more frequently than engine air filters.
How do I know when it's time to replace my air filter?
You should change your air filter when it gets dirty enough to restrict airflow to the engine, which reduces acceleration. When that will happen depends on where and how much you drive, but you (or your mechanic) should check the engine air filter at least once per year. If you frequently drive in an urban area or in dusty conditions, you'll probably need to change it more often than if you live in the country, where the air is typically cleaner and fresher.
Why do I need to change my air filter?
The filter cleans the air that goes into the engine, catching particles that could damage internal engine parts. Over time the filter will get dirty or clogged and restrict air flow. A dirty filter that restricts air flow will slow acceleration because the engine isn't getting enough air. EPA tests concluded that a clogged filter will hurt acceleration more than it hurts fuel economy.
How often should I replace my air filter?
Many manufacturers recommend every two years but say it should happen more often if most of your driving is done in an urban area with heavy traffic and poor air quality, or if you drive in frequently dusty conditions. Air filters aren't that expensive, so replacing them annually shouldn't break the bank.
How much should I pay?
The cost of repairs can depend on where you are as much as it does on what you need fixed. To get an estimate for your repair, go to our estimator, plug in your car's year, make and model information, add your ZIP code, and choose the repair you need. We'll give you a range for what your repairs should cost in your area.