Cabin Air Filter Replacement: 2003 BMW 325i 2.5L 6 Cyl. Wagon

The cabin air filter in your 2003 BMW 325i filters the air that is blown from your heater or air conditioner into the cabin of your 325i. How often to change the cabin air filter? Change your cabin air filter frequently: at least once a year or every 20,000 miles. If you drive in dusty conditions, lots of stop and go traffic or have sensitivities to pollen, road dust and pollution, change your cabin air filter more often. Replacing the cabin air filter (also known as the dust filter, hvac filter, pollen filter, air conditioner filter and hepa filter) will improve the air quality of your 325i, will put less strain on your heating and air conditioning system and can increase your gas mileage. These filters are fairly inexpensive, the cost of a cabin air filter is usually $10 - $30 (tip: buy several - they don't expire and you will be able to quickly swap the old one out for a fresh one). However, if you pay to have the cabin air filter changed for you, that can easily cost $50 - $100.

Not all BMWs have a cabin air filter and for some models, the inclusion of a cabin air filter depends on what trim level you have (Base). Newer cars are more likely to have a cabin air filter than older models. If your 325i has a funky odor when you turn on the heat or air conditioner, or it seems like the fan doesn't work as well as it used to, replacing your cabin air filter is a quick and cheap fix! Cabin air filter vs. air filter? The cabin air filter in a 325i refers to the filter that filters the air inside your vehicle (where you and your passengers sit); whereas the air filter filters the air that goes into your engine.