Most people do not feature the cabin air filter in their top priority list of replacement when performing general vehicle maintenance. It may not even be on the list. Indeed, many go as far as asking, what does a car air filter do? more often than not even when told in lay terms. Little wonder more popular car parts such as the oil filter and the engine air filter often overshadow cabin air filters.

Even on occasions when shown, some find it difficult to fully grasp the concept of air filtration, particularly in a car. It is, therefore, a well-known fact that many never change their car filter and do not know whether it exists. However, professional vehicle auto technicians say cabin air filters play a significant role and replacing it once in a while may prevent an expensive repair. In addition, a clogged or faulty cabin air filter is said to increase the pollutant concentration in the interior of a vehicle up to six times that of the outside air.

This article will now exclusively review all the details of a cabin air filter and its crucial role in the vehicle, trying to answer some of the most popular questions in this regard along the way.

What is a Cabin Air Filter?

The cabin air filter is a pleated filter with multi-fiber paper cotton and additional engineered materials. This filter is located under the dashboard or behind the glove compartment in most vehicles. You may wonder what cars have cabin air filters. Well, the answer is simple. All modern cars manufactured since 2000 have these cabin air filters, as it is an essential component that traps all the materials in the air that goes through the HVAC system.

Types of Cabin Air Filters

The various features of a cabin air filter determine its category. Some of the features considered include the fleece material used, the designs of the filters and the overall quality. Ideally, the material used should be five layers for excellent filtration while the filter media should trap 1/1000 microns. On this basis, the two types of cabin filters are electrostatic and charcoal filters. They both function efficiently but electrostatic filters can capture ultra-fine particles.

The History of Cabin Air Filters

The revolution of cabin air filters developed since 1985 in Germany. This was as a result of over 30 million registered vehicles contributing to increased air pollution during this period. The air especially directly over the road was tested and found to contain corrosive gases and particles. This type of contaminated air is not only harmful to car drivers only but also passengers causing headaches and loss of concentration as it flows through the ventilation system into the cabin. Along the way, MANN + HUMMEL Company progressively developed a cabin air filter to solve the puzzle of contaminated cabin air. Today, the current cabin air filter combines an adsorptive reduction of odors and corrosive gases through activated carbon and separation of particles; an effective way to reduce contamination in cars.

What Does a Cabin Air Filter Do?

The primary role of a cabin filter is to maintain a comfortable cabin for passengers by providing clean air. It filters the air that is taken into the air conditioning and heating system of the vehicle and prevents pollen, dust and other foreign particles from entering and polluting the vehicle cabin. The cabin air filters function the same way as the engine air filters hence gets dirty with time. As a result, it is advisable that cabin air filters are replaced at regular interval servicing to avoid becoming excessively contaminated.

Does Cabin Air Filter Affect A/C?

A dirty air filter will not only cause air pollution in the cabin but will also affect air conditioner (A/C) functionality. It supplies restricted airflow to the A/C system, which makes it work harder causing the motor to burn up in the process. Similarly, a dirty engine air filter reduces engine performance and vehicle efficiency. In both cases, repair will be more expensive hence, as they say, when it comes to cabin air filter problems, prevention will always be better than cure. For example, installing a new engine air filter can improve gas mileage by approximately ten per cent.

Symptoms of a Bad Cabin Air Filter

Now that you know the vital role played by the cabin air filter, how will you know when a visit to the advance auto parts store is required to replace a faulty or malfunctioning cabin air filter?

  1. Reduced airflow caused by a dirty cabin means that the air conditioning vents will blow with less force.
  2. Low cooling A/C capacity.
  3. Strained A/C blower motor will be strained.
  4. A dusty or musty odor coming from the car’s interior vents

All the above symptoms signify a lousy cabin air filter. Alternatively, it is advisable to change your cabin air filter every 12,000 miles (15,000 km) or yearly.


In conclusion, the cabin air filter should be replaced regularly to keep the A/C system efficient and the cabin comfortable for passengers. Many advanced auto parts stores offer a variety and you’ll find even more choices online via e-stores like Amazon or directly from a manufacturer’s website. If you have never replaced your cabin air filter or you suspect that it may be dirty, you should have your vehicle examined by your mechanic as soon as possible to know if it needs to be replaced. Cabin air filters can go for as little as $25 varying on the car model. High-end car model filters such as the BMC air filter can be a bit more expensive.

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