Most car owners naturally ask themselves from time to time when certain parts of their vehicle should be replaced. While oil changes and tire maintenance are commonly recognized tasks, fewer people consider the importance of replacing the pollen and air filters as part of regular car care.

Yet these filters not only affect the engine’s longevity but also significantly improve the air quality inside the cabin. In this article, we’ll explore why it’s important to replace them, what types of filters exist, and what to watch out for during maintenance.

What’s the difference between pollen and air filters?

There are two different filters in a vehicle, each serving an important purpose. The engine air filter cleans the air entering the engine, removing dust, insects, and other particles. When the filter becomes clogged or worn out, engine performance suffers, fuel consumption may increase, and in some cases, it can even lead to engine damage. A neglected air filter can pose serious safety risks over time.

In contrast, the pollen filter (also known as a cabin air filter) purifies the air entering the passenger compartment. It filters out dust, pollen, exhaust particles, and — in more advanced versions — even bacteria, mold, and odors. This is particularly important for allergy sufferers, families with young children, or those driving in urban environments.

Why is regular replacement important?

Filters gradually become saturated during use. A clogged filter becomes less effective, making replacement not only necessary but eventually unavoidable. Some of the main consequences include:
•    Reduced airflow to the engine, resulting in decreased performance and increased fuel consumption;
•    Weaker air conditioning performance, foggy windows, and unpleasant odors in the cabin;
•    Increased health risks for passengers, as the filter can no longer capture airborne allergens and pollutants.

Especially in summer, when we rely heavily on air conditioning, filter maintenance is crucial for both comfort and health.

How often should they be replaced?

As a general rule, both air and pollen filters should be replaced every 15,000–20,000 kilometers (about 9,000–12,000 miles) or once a year, whichever comes first. However, if you often drive in dusty or urban environments, or take frequent short trips, more frequent replacement may be necessary.

Signs that a replacement may be due include:
•    Unpleasant odors in the cabin;
•    Weak airflow from the vents;
•    Fogged-up windows;
•    Sneezing or itchy eyes while driving.

What types of filters are available?

When choosing a filter, it’s important to consider the vehicle type, driving environment, and the passengers’ sensitivities. In general, your needs and expectations will guide your decision. The most common filter types are:
•    Basic paper filters: Made from pleated cellulose or synthetic materials. They are affordable but have limited filtering capacity, making them ideal for frequent replacement. Their main advantage is their wide availability for nearly all vehicle models.
•    Activated carbon filters: These improved filters have an additional layer of activated carbon that can absorb odors and certain gaseous pollutants from the air. They offer a great balance between price and performance.
•    HEPA filters: Representing the most advanced filtering technology, these filters are made from special microfiber material capable of capturing at least 99.97% of particles as small as 0.3 microns. HEPA filters are used in hospital equipment and air purifiers. Their key benefit is outstanding filtering efficiency, though they come at a higher price and are not available for every vehicle model. Still, they are highly recommended for frequent drivers, allergy sufferers, and those with respiratory issues.

The replacement process

The engine air filter is usually located in the engine bay inside a plastic housing, while the pollen filter is typically found inside the cabin — behind the glove compartment or beneath the dashboard.
Replacing these filters is generally quick and easy, and can often be done at home with basic tools and some care. Make sure to install the new filter in the correct direction — there’s usually an arrow on the filter indicating the direction of airflow. During replacement, it’s a good idea to check the cleanliness of the filter housing; a quick wipe can greatly improve the effectiveness of the new filter.
However, if you’re unsure, if the filter is hard to reach, or if your vehicle is under warranty, it may be best to have the job done by a professional.
A well-timed filter change not only ensures cleaner air but can also result in quieter, more efficient operation and a more pleasant driving experience.

In Summary

Replacing air and pollen filters is a maintenance task that improves both safety and comfort. It’s especially worth doing in spring, before allergy season, and in autumn, ahead of the heating season. With just a bit of attention, you can enjoy clean and comfortable driving for the long term.