How Often Should You Change Your Air Filter in Your Car?

March 31st, 2021 by

Regular service on your car helps your car run better, longer. Maintenance to your vehicle includes oil changes, fluid checks and fills, tire rotation, brake inspections, and air filter replacement. Regularly servicing your car improves your car’s efficiency and safety and extends the life of your vehicle.

Of the service items above, air filters get overlooked the most. So, how often should you change your air filter? Let’s take a closer look at what your air filter does, why you should change it, and how often.

What Is an Air Filter?

clean air filter next to dirty air filter

Image via Flickr by pauljoelhancock

Most cars have two air filters, one for the engine and the other for the cabin. Both filters need replacing as part of your normal maintenance.

Cabin Air Filter

The cabin air filter keeps the air in your car clean. Most air conditioners have a recirculated option or an outside air option. Your cabin air filter helps remove dust particles and allergens from the recirculated air. If you or someone who rides with you often suffer from allergies, a clean air filter can help prevent a possible allergic reaction. If you’re pulling air from the outside, that air carries pollutants into your vehicle. A clean air filter helps prevent you and your passengers from inhaling these dangerous toxins.

Engine Air Filter

Most engines are naturally aspirated. That means your engine breathes in the air as part of the combustion process. Your engine air filter helps keep dirt, dust, and debris from getting sucked in. These contaminants can harm your engine over time. A clean engine air filter will result in better gas mileage, more power, and better emissions.

How Often Should You Change Your Air Filters?

Your owner’s manual will tell you exactly when to change your filter. At Sweeney Cars, we recommend changing your cabin air filter at least once a year. If you drive more than 15,000 miles a year, then you should change it more often. It’s a good idea to budget for annual service like air filter replacement, and we suggest doing so in the Spring. It would be best if you started the pollen season with a fresh air filter.

Your engine air filter typically lasts from 15,000 to 30,000 miles. Your owner’s manual will give you the exact number. If you drive in heavy traffic, hot weather, or on unpaved roads, you should change your engine air filter more often. We also recommend doing this annually. When you bring your car in for an oil change at Sweeney Cars, we inspect your air filters and will recommend changing them if necessary.

Negative Impact of Dirty Air Filters

Experts agree that a dirty engine air filter will affect your engine’s performance in several ways. First, it reduces acceleration. This reduction isn’t easy to catch because it’s a gradual process. The more clean air that flows through the filter, the more power your engine can produce. As the filter becomes clogged, less air goes through to the engine, reducing its capacity. Slowly, your engine won’t accelerate as it should.

Your engine’s emissions will rise with a dirty air filter. Contaminants that make it into your engine ignite with the gasoline. The byproducts of burned contaminants can clog your exhaust ports and tubes. You might notice black smoke coming from your exhaust as a result. Fuel economy can also suffer from a dirty air filter, though experts are at odds with exactly how much.

The same holds for your cabin air filter. The gradual filtering process allows less clean air through the filter until you aren’t getting the same quality air you should. Unlike the engine, you breathe the cabin air. You may not notice a significant difference in the air quality at first, but over time you will. You’ll also be able to smell outside pollutants like exhaust from other cars or smoke from a factory you drive by often.

Signs You Need To Replace Your Filter

Visually inspecting your air filters will help you identify when it’s time to change them. Often, they are dusty or dirty, and your engine air filter could have road debris and even dead bugs in it. If you see these obvious signs, you should bring your car to Sweeney Cars for filter replacement.

A visual inspection doesn’t always tell the whole story. Your air filter may look clean but need replacing. Going by your owner’s manual recommendation will help you avoid a drop-off in engine performance and cabin air quality.

If you don’t already track your car’s gas mileage, we recommend you start. You’ll notice the mileage drop slowly at first. The longer you go between engine air filter replacement, the more precipitous the decline.

If your engine struggles to start, you might need to replace your engine air filter. A clogged filter won’t allow enough air into the system for proper combustion. Your spark plugs can get clogged up too from a clogged filter, further impeding your engine’s ability to start and run smoothly. If you experience any trouble like this, you should immediately bring your car to Sweeney Cars for a vehicle inspection. We’ll do a multi-point inspection and provide you a detailed breakdown of parts and labor necessary to get you back up and running at peak efficiency.

How Much Does a New Air Filter Cost?

A car’s engine air filter costs around $15 to $25 in most cases. Not replacing the engine air filter can lead to more significant repair issues in the long run. Even if it cost $50, the improved performance and longer engine life far out-weighs the expense.

A cabin air filter costs a little more, perhaps $40 to $70, depending on your car’s make and model. These filters cost more because they do more for air quality than your engine air filter. Not replacing them can lead to asthma and other health issues. If you suffer from allergies, your cabin air filter needs regular replacement to help reduce your symptoms.

At Sweeney Cars, we understand how regular maintenance impacts you, your passengers, and your engine’s performance. That’s why we check your engine and cabin air filters on every maintenance visit. Our factory-trained technicians are experts in identifying problems with all your car’s systems. You can schedule service online or bring your car in anytime. We’ll give your car the care it needs and you deserve, and have you back to your busy life in no time.

Posted in Service