1. Getting Started - Prepare for the repair
2. Remove Filter - How to access the old cabin air filter
3. Assess Filter - Determine if your old filter needs replacement
4. Replace Filter - Insert the filter and put everything back in place
5. More Info. - Additional thoughts on checking the cabin air filter
The cabin air filter (also known as the pollen filter, AC filter, dust filter, hvac filter and hepa filter) in your 2004 Ford Focus cleans the air that you and your passengers breath inside of your car. You need to change it at least once a year or every 20,000 miles, whichever comes first. In addition to improving the air quality of your Focus, replacing your cabin air filter will put less strain on your heating and air conditioning system and can increase your gas mileage. These filters are fairly inexpensive, so check out our parts page for great deals on a new one (tip: buy several, when you go to check the cabin air filter on your Focus, you can easily swap it for a new one if it is dirty).
Not all Fords have a cabin air filter and for some models, the inclusion of a cabin air filter depends on what trim level you have (ZTS). If your Focus smells bad when you turn on the heater or air conditioner, or it seems like the fan doesn't blow air as well as it used to, replacing your cabin air filter is a likely the best fix! The video above shows you where the cabin air filter in your 2004 Focus is located and how to check it.
Hans Angermeier has produced over 100,000 videos showing drivers how to fix things on their cars. He has broad expertise on basic repair procedures covering the majority of cars on the road.
Learn where your air filter is located and how to determine if it needs to be changed.
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