Five Signs That Your Cabin Filter Is Not Working (and the Replacement Cost)

When it comes to vehicle service, the cabin air filter is often overlooked and not well understood by many.

A cabin filter that is clogged can have a significant impact on the comfort and safety of your vehicle.

We will cover everything about cabin air filters in our guide.

Let's talk about its function, whereabouts, cost of replacement, and what you need to do when deciding if it's time for replacement. Let’s begin with a quick look at the signs.

Bad cabin air filter Symptoms

The most common symptom of a bad cabin air filter is a bad smell in your car’s cabin. A bad filter could cause fogging or icy windows in the morning. Also, if the airflow through the vents is very low, it’s definitely time to replace the filter.

Below is a list that explains the symptoms most commonly associated with a poor cabin air filter.

1. Bad Smell

A bad cabin air filter will cause a terrible odour inside your vehicle. After a while, the cabin air filter collects dust and other particles from outside.

This will cause condensate to filter through the filter, which can get stuck. You might be able to see that this can cause mold to the filter over time. Therefore, you should replace it within the prescribed schedules.

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2. Low airflow through the vents

The next thing that you may notice is that the airflow’s efficiency through the vents has dropped recently. Because the cabin air filter filters out all air going into your car, this is what happens.

The filter can become clogged if it has been in use for long periods of time. This will cause less air to pass through the filter. Airflow can drop significantly and even cease to blow.

3. Window fogging or freezing

You know that water condense can get trapped in cabin air filters, which could lead to mold growth. Condense can build up in the filter, which could cause it to accumulate more frequently. This condense water will then get blown into your car's cabin.

If you are in colder countries, this will make the humidity in your cabin rise. This can cause fogging or even freezing windows. It is time to inspect the cabin air filter if you have noticed foggy windows or icy windows lately.

4. Allergy symptoms

A bad cabin air filter can make your allergies worse if there are many particles in the environment.

We have already mentioned that all dust particles, including those from the outdoors, will become trapped inside the cabin air filter. Even though they may not be on the outside of the filter they could still enter the vehicle and trigger allergy symptoms.

5. The air vents make a light whistling sound

Bad or clogged cabin filters can restrict airflow and cause strange sounds when air passes through them.

If you hear a whistling noise from the air vents that weren’t there before – it is definitely time to inspect the cabin air filter and replace it if it’s bad.

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What's a Cabin Filter?

Your car's cabin air filter filters out harmful contaminants like dust, pollen, and other pollutants. The filter also helps to prevent leaves or other dust getting trapped in the motor.

The car draws air in from the outdoors and directs it towards your vehicle. There are many harmful particles and dust in the air, so a filter is necessary to get rid of them.

The filter also stops leaves or other dust getting stuck to the motor. This could create a horrible noise inside your car – which you probably already noticed if you owned an older car without a cabin air filter before.

So now, when you know what a cabin air filter is, let’s find out what will happen if you do not replace the filter in time.

How frequently should the cabin filter be replaced?

Activated charcoal cabin air filters should be replaced once a year or every 15.000 miles (24000 km). Air filters for standard particulate should be changed every 2 years or 30.000 km (48000 km).

To know when exactly to replace the cabin filter for your specific car model, you must consult the manufacturer’s repair manual or call your dealer to get the correct information for your vehicle.

It also depends on the climate where you live. It will be more difficult to replace your air conditioner if it is in dusty conditions than you would if you lived in clean climates.

The cabin filter is often very inexpensive and should be replaced every year.

What happens to the cabin air filter if it is not replaced?

The cabin filter can cause symptoms including a bad odor, low airflow, foggy windows or icy windows inside the cabin, allergy or whistling sounds from the outside.

Bad smells in cars can quickly get trapped in the interior, which may cause a decrease in car's worth and even permanent damage to the air conditioner. It is important to ensure that your cabin air filters are kept current.

Is the cabin air filter found where?

Most cars have the cabin air filter hidden behind the glovebox or under the cover that covers the engine bay. You can find the location of your blower motor by looking closely!

For many models of car, the glove box must be removed to reach the filter. Most cabin filter companies will provide instructions for how to change the cabin filter on your car's model.

Most Asian cars have the cabin filter behind the glove. In some cases the glove must be taken out to replace it.

In European cars, it is usually hidden behind the cover that covers the engine bay.

RELATED: No Heat in the Cabin – Common Reasons & Fixes

Air Filter Repair Costs

An average cost to replace a cabin filter is $40-$100, depending on car make and labor costs. A cabin air filter can cost $20-$50 depending on whether you buy a standard or charcoal filter.

Cabin air filters are often replaced at a very low labor cost. In most cases the process takes less than 30 minutes.

A standard or charcoal cabin filter will have a different price than a charcoal one. The charcoal filters filter the air more effectively and can be used by people suffering from allergies.

Cabin Air Filter FAQs