Cars are complex machines. For this reason, many people have questions about specific parts of their car and how necessary they’re for the overall driving experience, and we’ve answered a great number of them, whether it’s unsafe to drive a car without a differential, a catalytic converter, and many more!
Today, we will look at the cabin air filter (not to be confused with the air filter). Let’s start with a quick answer to our main question:
Can you drive your car without a cabin air filter?
You can drive without a cabin air filter; it doesn’t affect your car’s performance. However, it will affect the air quality in your car’s cabin. Without this filter, you and your passenger will breathe in contaminated air. Plus, the contaminants the filter is supposed to trap will enter your HVAC system and destroy it.
However, that certainly doesn’t answer the question entirely. In the article below, we’ll thoroughly discuss the use of a cabin air filter and what health and/or safety risks there are when driving without one.
Furthermore, we’ll discuss how good cabin air filters filter, if it’s illegal to drive without one, how you know when to replace them, and what you can expect when driving without one. Read on!
What Is A Cabin Air Filter And What Does It Do?
A cabin air filter is a device found in the heating and cooling system of many vehicles. It’s made out of fibrous materials and works to trap organic compounds such as benzene, toluene, ethylbenzene, and xylene isomers (BTEX) from the air and prevents them from entering the vehicle through the HVAC system. This way, you and your passengers won’t have to breathe contaminated air while driving.
It is located under the glovebox in many vehicles and cleanses the air as it goes through the HVAC system. In other cars, you may find it under the hood or behind the dashboard—more on the location of the cabin air filter at the end of the article.
Is It Safe To Drive Without A Cabin Air Filter?
From a health perspective, it’s unsafe to drive without a cabin air filter; however, people still drive without it. Pollutants such as dust, engine fumes, dirt, twigs, leaves, and debris in the air are trapped by this filter. When the filter is not intact, these pollutants enter your car and contaminate the air you breathe.
Inhaling contaminated air could cause serious health problems for you and anyone in the car. Studies have shown that the short- and long-term exposure to various levels of particulate matter and black carbon is linked to acute respiratory system responses (e.g., allergy, asthma, and inflammation) and even mortality. In addition, various volatile organic compounds (VOCs), such as benzene, are known for causing cancer in humans.
Is It Illegal To Drive Without A Cabin Air Filter?
In the United States, it’s not illegal to drive without a cabin air filter. The reason for this is that you’re not posing to be a safety risk to other users of the road. Furthermore, authorities can’t see if you’re driving without a cabin air filter from the outside of the car.
Should You Drive Without A Cabin Air Filter?
I will not advise you to drive without the cabin air filter. Without it, pollutants like pollen, dust, and other debris will enter your car and contaminate the air inside the car. Breathing polluted air will cause different health ailments. This is not only the case for yourself but most likely also for your partner, family, friends, or kids.
Furthermore, when these pollutants enter the HVAC system directly, it damages its components. And in the end, you will need to spend money on replacing them. A cabin air filter only costs $20 – $50 and is very easy to replace, whereas severe damage to the HVAC system can render it useless, so you need to replace it, typically costing $1,000 – $1,500.
How Effective Are Cabin Air Filters At Filter Contaminants?
In one study, it was found that cabin air filters have different efficiencies depending on the particle size that’s being filtered. Eleven filters were researched, and it was found that all of them had a filter efficiency of 78 – 94% for particles with a size of 6nm. Filter efficiency indicates the percentage of particles that were filtered out of the air.
For particles with sizes of 520nm, filter efficiency between all cabin air filters was found to be 35 – 60%. The best filters filtered the hardest to filter particles (100 – 300nm) at an efficiency of 44 – 46%, whereas the worst filters achieved a filter efficiency of 10-11%.
According to this study, electrostatic filters provided a 20 – 60% better filter efficiency than other cabin air filters across all particle diameters (6 – 520nm). However, the benefits of an electrostatic filter dissipate after one year of use, after which it achieves similar filter efficiency as all other filters.
Why Are You Driving Without A Cabin Air Filter?
If you are driving without the cabin air filter, it could be that:
- Your filter is faulty
- It’s dirty or clogged
- Or your car was manufactured without a cabin air filter (cabin air filters only really became a thing since the 2000s)
For a faulty cabin filter, replacing it will be the best option as it is cheap and easy to replace. For clogged or dirty filters, checking periodically and cleaning will make you breathe in the fresh air. Check your car’s owner’s manual on how to clean your cabin air filter, or check the video below, which explains how to get the cabin air filter out and how to clean it.
If your car comes without a filter, you shouldn’t have to worry. Not all vehicles are manufactured with cabin air filters. However, cars like that have HVAC systems built differently to withstand these pollutants without straining the system. However, they’re not as effective as cabin air filters, so many people then opt for a DIY solution.
Why Does Your Cabin Air Filter Fail?
When your cabin air filter fails, it no longer functions as it’s supposed to work. This means something is wrong with the filter, and you expect to take specific actions. Possible causes of filter failure may include:
Lack Of Maintenance
The filter’s job is to trap contaminants in the air that enters your vehicle. In doing so, only fresh air enters your car. And as it carries out this task, it gets clogged or dirty. Yes! It is made to get dirty.
However, you are not supposed to leave it dirty. If you do not check the filter, these trapped pollutants pile up in large quantities over time, thus blocking the filter. When the filter is clogged, airflow becomes restricted, and the filter may start emitting foul smells. When these start happening, know that your filter is faulty or failing.
To avoid this, ensure you regularly check your cabin filter and remove any impurities. A cabin air filter lasts around 15,000 – 30,000 miles (check your owner manual). Therefore, cleaning it once a year isn’t a bad idea. This way, you and your passengers can breathe fresh, clean air.
However, replacing the cabin air filter every six months might be your best bet for those who drive through dusty areas. Furthermore, if you notice any of the symptoms of a faulty filter (we’ve mentioned below) before the recommended time, you will need to repair or replace them immediately.
Poor Quality Materials
Most cars come with a good quality filter. But if you used a low-quality product during replacement, it may not function properly. To avoid this, always use original filters during replacement. A simple Google search will tell you your car’s OEM filters.
What Are The Symptoms Of A Failing Cabin Air Filter?
When your filter is failing, you may start experiencing some unusual activity in your car. When a filter is broken, clogged, or too old and weak, its performance is limited.
Below are some common signs that tell your filter is failing, and you may need to fix it.
Inadequate Airflow From Vent
Inadequate airflow from the vent might indicate that the filter needs to be checked and fixed.
Airflow is restricted chiefly when the filter is blocked with dirt accumulating over time. So long the filter is contaminated, it won’t filter the air as it should.
This restricted airflow from the A.C system makes the vents blow air without force, straining the car’s A.C system.
Unusual Odor From Car’s Vent
The foul smell from your car’s vent indicates that your filter may need fixing.
With time, a clogged or dirty filter will emit dusty or musty smells from the vehicle’s interior vents.
And the smell even gets worse when you try to increase your A.C system airflow. So what can you do here?
You should check for dirt in the filter and clean and replace it. If you don’t, the smell will make the car uncomfortable for you and your passengers.
Coughing While Car Is Running
When your cabin filter is faulty, it will not filter harmful particles from the air entering your car. And as such, these impurities find their way into your car and contaminate the air you breathe. This leads to coughing.
Itchy Eyes Or Nose
Pollutants that a faulty or worn-out filter couldn’t trap enters your car and pollute the air. And as such, your eyes and nose may start itching as you drive.
Furthermore, suppose you are allergic to specific particles. In that case, it will only worsen if the filter is too old, clogged, or damaged because the filtered particles will get stuck, or the filter cannot filter the air properly. Hence, particles will find their way into your car and cause allergy symptoms.
Increased Fan Noises
When your car’s A.C system is on, you should hear a clear sound from the vent. This clear sound indicates that the fan and A.C system are in perfect condition. However, if you start hearing a sharp fan noise, it shows your filter isn’t working well.
Large particles in the filter make it difficult for air to enter your car and properly filter. As a result, it emits a lot of noise as air passes through it. So whenever your fan is on, a loud noise is what you hear.
Ensure those large particles are removed because the noise will only intensify with time.
Foggy Or Icy Windows
The cabin filters work to control airflow in the car and also clear fog and ice from windows. When the filter isn’t working well, the airflow weakens. This weakened airflow causes the car’s system not to function well. Making it difficult for it to eliminate moisture from the windows.
Because of this, your windows would retain ice and fog for a longer time. This poses a potential danger while driving because you won’t see clearly.
Problem With The Heating And Cooling
Clogged filters will always fail to function appropriately. This is because as the filter clogs, it reduces HVAC efficiency and the A.C airflow system.
And as a result, the cooling and heating ability of your car reduces. In turn, this strains the HVAC system, which can cause possible blowouts.
Again, reduced airflow makes it hard to adjust the temperature within the car. This inability to change temperature makes passengers uncomfortable when there is a change in season.
Where Is Your Cabin Air Filter Located
Typically, the cabin air filter is supposed to be around the A.C system to filter air entering the vehicle. But some car manufacturers placed it in positions where they can help filter recirculated air. This, however, depends on where the recirculation door is placed.
So you will likely find your cabin air filter in any of these places
- Behind the glovebox (the case for most cars): To access the filter, remove the small panel at the back of the glove box.
- Under the hood: many cars get their air through the windshield cowl. To access the filter, raise the hood and take off the plastic lid.
- Behind the dash: In a few cars, you will find the cabin air filter around the dash. In others, you will see it on the passenger’s flank, above or underneath the glove box. Few can be found on the driver’s side.
What Is The Replacement Cost For Cabin Air Filters?
The cost of replacing a cabin air filter is usually between $40 and $100. This cost depends on your car model, the type of filter you want, and labor cost.
The filter cost is around $15-$55, with the labor costing between $25-$45. It will take less than forty minutes to get this job done.
The cost of the filter depends on whether you need an electrostatic, charcoal, or standard cabin air filter. Electrostatic cabin filters cleanse the air better and are the best option for people with allergies.
You can do it yourself if you want to, locate the filter in your car and fix it. Just check your owner’s manual for the location and directions on how to replace it. But if you cannot do this task, you can refer to a good mechanic.
Hi! My name is Stefan; I’m the owner and lead writer at TheDriverAdviser.com.
I’m an active writer on this blog myself, as well as a novice car mechanic. For the really technical stuff, I find writers with experience as a mechanic or who have studied mechanical engineering.
Read more about our fantastic team on our about page!