Most vehicle owners do the bare minimum. They put gas in it to get from point A to point B, and they get the oil changed when the little light on the dash starts to blink. That’s great, but there’s so much more. Engine air filters are one of the most important things you can do for your engine. Your engine needs air in addition to fuel in order to work properly.
An engine air filter filters the air coming into your engine and is important to the smooth operation of your engine. The cleaner and colder the air is, the more optimally your engine will perform, so it’s important that your engine air filter is cleaned or changed out frequently.
Up Front Best Car Air Filters
- K&N 33-2031-2 High-Performance Air Filter: Best Overall
- Fram CA4309 Extra Guard Air Filter: Provides Excellent Engine Protection
- AEM 28-20304 DryFlow Air Filter: Best for Increasing Engine’s Performance
What is an Engine Air Filter?
An engine air filter defends your engine against dirt, dust, and debris. If these particles were to enter your engine, it could cost you thousands in repairs. This pleated, rectangular-shaped filter is located at the front of your engine compartment. It’s housed inside a cold air collection box and traps particles in the air before they flow into your engine.
While small amounts of dirt are harmless, your engine needs massive amounts of clean air to operate efficiently, and without it, it won’t run efficiently, or at all. The more unfiltered air you expose your engine to, the faster it will wear out.
Dust can damage the engine’s internal components, which means you end up replacing the entire engine because it’s simply not cost-effective to replace worn internal components by themselves.
Benefits of Changing the Engine Air Filter
You should change your engine air filter every 15,000 miles, and more frequently if you live in a rural area or on a gravel road where it’s dustier. This helps to maintain clean airflow to your engine.
The benefits of keeping airflow to your engine clean are:
- Better acceleration – As you might imagine, when your engine is struggling, your car isn’t going to see the performance it would if your engine were performing at its peak. With a clean air filter and clean air, your engine will operate optimally, which means you’ll notice better acceleration and a whole lot of other enhanced performance.
- Improved fuel economy – When you replace the engine air filter, you increase the amount of clean air that flows to your engine. That means the fuel combusts more efficiently, so you spend less money on gas.
- Longer engine life – When your filter is clean and working properly, the air your engine receives is also clean. That means your engine can work properly and it will last longer without getting dirty or damaged by particles. Filters can increase engine life by protecting them from dirt and dust that damage the fuel system, pistons, and other components.
- Reduced emissions thanks to a correct air/fuel mixture – Not only are you keeping dirt out of your engine, but you’re keeping it out of the combustion process, too. Your engine can burn cleaner, which means your exhaust is cleaner.
- Low cost – Many of your car’s components cost a lot of money, but engine air filters are surprisingly affordable. Most of them cost less than $50.
Types of Engine Air Filters
You have several options to choose from when it comes to engine air filters. You’re not restricted by just one kind, because there’s a lot of variety in car parts these days.
As with many other types of parts, replaceable options are the most common. These are available in a wide variety of brands and are typically the most affordable.
They’re made of a material that feels a lot like paper. It’s a porous, fibrous-like material that’s square or rectangle, and accordion-shaped, to offer a bigger surface area to catch as much debris as possible.
These replaceable filters can collect a very large amount of large and small particles and should be changed frequently.
Another very common type of filter is a reusable filter. It’s also made of a cloth-like material, but it can be cleaned and reused for the life of the car. They’re washable and can very easily collect a lot of debris of all sizes.
They’re great for the environment because you don’t discard them. You simply wash them and reuse them. You pay more for them up front, but they’re worth it in the long run.
There are plenty of top brands on the market when it comes to engine air filters. Many of these brands have been around for 50 years or more and are trusted in the automotive industry by professionals everywhere.
Fram is based in Lake Forest, Illinois, and has been in business since 1932. Their air filters are some of the most popular on the market and they even received the Army-Navy “E” Award in 1945 for patriotic service during World War II.
This award gave them exclusive rights to produce filters for the military.
One of the most popular modern brands is K&N Engineering. They began in 1969 in Riverside, California, and grew quickly by focusing on producing air filters and other products based on filtration.
Today, they are one of the biggest and best car air filter brands in the world. They have factories all over, including China, the Netherlands, and England. They are known for their high flow air filters.
AEM Induction Systems
Bob Sullivan and John Concialdi started AEM in 1987. It was a high-performance automotive tuning shop in Compton, California, but has since focused on creating the best air filters used on the racetrack and privately.
Here are some of the features you might want to look for when shopping around for your next engine air filter.
What your engine air filter is made of makes a bigger difference than you think. What it uses to collect dirt and debris is the biggest distinguishing feature among all the brands and types of filters out there.
Most are paper because it’s cheap to produce and it’s easy to make. Plus, with the wide variety of disposable filters on the market, you’re going to find that the majority of them are made of paper.
However, other types include cotton, foam, carbon fiber, and steel mesh. Do some research to find out who makes them and what the benefits are because you may be surprised. If you’re looking for a reusable one, you can find some relatively affordable options that still work great.
The shape matters, too, for a very interesting reason. Different car manufacturers accommodate different sizes and shapes, but some high-performance filters are made in a conical shape to force air through faster.
This increases your horsepower. The faster you can deliver cold air to your engine, the more you can increase your performance. The most important thing is that you know the dimensions you need prior to buying your filter.
Filters will feature several layers of their chosen media. It gives your engine a few extra layers of protection. They come in all sizes, shapes, medias, and price points. You don’t have to spend a lot of money to get a quality filter.
Engine air filters come at a variety of price points. At around $10 or $20, you can some of the best affordable, disposable filters. While you won’t find reusable filters at this price, you can get high-quality disposable filters that will give you great protection.
If you look from $20 to $60, you’ll find multiple layers of protection and expensive synthetic media. There are also some fantastic reusable filters at this price point.
Moving up from here you’ll find high-end filters and luxury options for professional drivers. Carbon fiber filters with multiple layers of protection and plenty of replaceable filters live here.
If you’re in the market for an engine air filter and you’re not sure what to get, here are some of the best options on the market today.
By far, one of the best overall picks is the K&N high-performance filter. It’s specifically designed to boost the performance of your engine. It can increase your horsepower and your acceleration. Plus, you never have to replace it. K&N filters are reusable. Just wash it off and put it back in. It comes with a 10-year, 1-million mile limited warranty.
K&N’s design was developed through years of use in desert motocross racing. They are made of six layers of tightly packed cotton and held in place with two layers of wire mesh. This high flow material is washable and still works perfectly after 100 washes.
The Fram Extra Guard Filter offers a great value for the price that offers excellent protection for your engine. It’s a replaceable filter that gives you more protection than comparable filters. If you change it regularly, you’ll get twice the protection at the same cost.
This filter is made of a paper-mesh grille interwoven with wire meshing. It can filter out microscopic particles, protecting your engine from even the smallest debris. The size of the surface area ensures it collects nearly everything.
While this filter doesn’t fit every vehicle and the occasional factory defect can have you frustrated, you can always return it for a new one. It also doesn’t come with instructions, so if you’re not sure what to do, have a professional help you.
This AEM filter is made of a washable synthetic material. It’s designed to increase your engine’s performance. The material is so durable, that they’re sure you’ll never have to buy another. In fact, they’ve backed it with a limited warranty to prove it.
It adds acceleration and top-end with its high-performance design made of an intricate web of carbon fiber. It catches all shapes and sizes of particles while still allowing for excellent airflow. The only issue with this filter is that it sometimes doesn’t fit into the vehicles it says it’s designed for. The rubber edging sometimes fits too snugly.
AEM Air Filters are cleanable and guaranteed for the life of your vehicle. Designed to increase horsepower and throttle response.
Signs of a Dirty Engine Air Filter
Wondering how to tell if you need to replace that air filter already? There are several telltale signs.
1. Reduced fuel economy
If you’ve noticed having to fill up more often or not being able to go as far on a tank of gas, it may be time to change your engine air filter again. If your engine isn’t getting enough clean air, it will compensate for a lack of power by using more fuel.
However, this is really only significantly true for carbureted cars manufactured before 1980. Because carburetors work by mixing air and fuel at the ideal radio for an internal combustion engine, you may notice increased fuel consumption.
Newer cars have fuel injection engines that use computers to calculate air intake. It adjusts the fuel flow accordingly, and usually won’t affect gas mileage as much, but it could.
2. Unusual engine sounds
If your car is running as it should, you’ll notice smooth idling. If your car isn’t moving, but it’s turned on, you’ll hear a smooth rotation of the engine and feel subtle vibrations. However, if you feel it vibrating roughly, coughing, or popping, it could mean your air filter is clogged, which could cause a dirty or damaged engine to act abnormally.
3. Misfiring engine
When your air filter is dirty, it restricts the air supply to your engine, causing some of the fuel injected into the engine to pass through unburnt. As it passes through, it exits the engine as soot residue.
The soot residue accumulates on the spark plug, which then can’t perform its job of delivering the spark that combusts the air-fuel mixture. As a result, the engine won’t start very easily, it will misfire, or it will jerk roughly while driving.
4. Check engine light turns on
Modern engines will consume about 10,000 gallons of air for every gallon of fuel they burn. An inadequate air supply, which is the result of a dirty filter, can cause carbon deposits, the result of combustion, to accumulate on the engine, which will set off your check engine light.
As always, if your check engine light is on, you should have a mechanic run some diagnostics to make sure nothing more serious is going on because there are a variety of reasons the check engine light could be on.
5. Reduced horsepower
If you notice that your car doesn’t respond to pressing the accelerator like it used to or it responds in jerking movements, your engine may not be getting the air it needs. Replacing your engine air filter can actually improve horsepower and acceleration by about 10%.
6. Gas smell when starting the car
If not enough oxygen passes through the system when you start the car, the unburnt fuel will exit through your exhaust and it will smell like gasoline. This is a pretty clear indicator that it’s past time to change your engine air filter.
7. Smoke or flames coming from the exhaust
Even worse sometimes, are flames coming from your exhaust. It may sound Greased Lightning, but that’s not supposed to happen. When your engine doesn’t get enough air, the fuel won’t burn off completely, so it will exit your car through the exhaust and come out as black smoke or flames.
You may also hear popping sounds, which some people call a backfire. This is a pretty dangerous condition and you should have it taken care of right away.
8. Dirty engine air filter
One of the easiest ways to tell if you need to replace your engine air filter is to take it out and look at it. They’re normally white or off white when they’re new. If it’s dirty, it needs to be changed.
However, sometimes layered engine air filters may have dirt, debris, or microscopic particles on the inner layers that you can’t see, so if you’re not sure what you’re looking at, you should have a professional check it out.
Where to Buy
Engine air filters are easy to come by. You can get them at virtually any auto parts store in town. If you want to replace it yourself, you can order it online at places like Walmart, Amazon, O’Reilly, Napa, Auto Zone, or straight from the manufacturer.
If you feel more comfortable having someone install it for you, you’re better off taking your car to a local mechanic or any place that works on cars locally. Those places include Walmart, the car dealership, Valvoline, Firestone, and much more.
Here are just a few extra tips when you’re thinking about engine air filters:
- It’s sometimes too easy to forget when you changed it last, so you’ll need to find an easy place to make a note of when you changed it last. You can keep it with your car’s paperwork, put a reminder on your calendar, or tape a sticky note to your windshield with your oil change reminder.
- For some people, a high-performance engine air filter is beneficial, and for others, it’s not. Do some research first to see what some of the benefits might be. Don’t spend the money if you don’t think it’s worth it for you.
- If you decide to go with a replacement engine air filter, you may also want to consider using a higher octane fuel as well. It can help ensure that your engine maintains clean and powerful combustion as well.
How many miles can I go between engine air filter changes?
You shouldn’t go more than 15,000 miles or so before you change your engine air filter if you’re using a disposable option. You may want to look at your owner’s manual for more information or ask a trusted mechanic.
However, if you’re using a filter that is washable, you can take it out when it gets dirty and wash it. No need to replace it.
Can I cut my air filter to fit in my car’s filter cabin?
Air filters are designed to handle a lot of airflow. If you alter the design, it will weaken the structure, which will reduce its effectiveness and the life of the product. It’s better to get an air filter that fits your car.
How do I wash reusable air filters?
Use soap and water on your dirty engine air filter. If it’s very dirty, you can try a degreaser. Don’t be too rough with it and don’t use any abrasive materials. Simply rub gently, rinse, and reapply soap as many times as needed.
Shake the water off and let it air dry before reinserting it.
What happens if you don’t change your engine air filter?
When your engine air filter gets dirty, it will get clogged. Air won’t be able to pass through into the engine, which means your engine has to use fuel to compensate for the lack of air, which results in poor performance and a drop in fuel efficiency.
Engine air filters are critical to the safe and efficient operation of most cars today. Whether it’s ensuring that your engine functions properly or you experience a higher output of horsepower in your performance vehicle, a high-quality engine air filter will go a long way.
There are plenty of different varieties to choose from, but there’s no shortage of options within your price range. It’s important to consider what matters most to you, and once you’ve done that, you’ll be able to find the right product without much trouble.