Search By Vehicle
Search By Dimension

The Best Engine Air Filters For Your Car

Your car’s air filter is key to the performance and long-term health of your engine. It is a critical element of your engine’s air intake system, and is designed to allow steady airflow into your engine while simultaneously filtering out damaging particulates. The filter helps ensure that the pistons, cylinder walls, and sensors in your engine perform their best, reducing the chance of costly maintenance. An air filter can also help optimize the amount of clean air flowing into your engine. Clean air is critical to the combustion process, which means that your air filter can have a significant impact on your vehicle’s horsepower. That’s the muscle and acceleration we’re all looking for.

How is a reusable air filter different from a paper air filter?

Single-Use Paper Filters
The typical disposable paper air filter that comes standard with most cars is typically made of pleated paper set into a plastic or foam frame. It’s low-cost, efficient, and designed to be thrown away after a relatively short service interval. Most last roughly 12-15,000 miles under normal driving conditions before they must be replaced. Single-use paper filters contain masses of tiny pores that block larger particles - dust, pollen, pollution - while letting smaller ones through. Over time, those pores in the media become clogged, restricting airflow into your engine and reducing overall performance and efficiency. You might notice more sluggish performance, slower acceleration, and lower fuel efficiency, which can all be signs that you may need to replace your filter.

The benefits of reusable High-Flow Air Filters™
K&N® High-Flow Air Filters™ are composed of 4-6 layers of breathable cotton gauze, which is pleated to increase the contaminant-capturing surface area. Their state-of-the-art design and naturally breathable properties allow for an increased flow of clean air into the engine — which often translates to increased horsepower and performance. K&N pleated cotton filters are saturated with K&N’s trademark Red 201 Filter Oil™, which is then suspended within thousands of microscopic cotton fibers. This innovative system helps to trap dirt and contaminants without blocking the pores of the filter. In fact, the oil not only traps unwanted contaminants, but those pollutants, now sticky with oil, begin to trap other particles, effectively becoming part of the filtration system. The result is a significant increase in the volume of clean air flowing into your engine - up to 50% more air than traditional, single-use filters.

Unlike single-use paper filters, K&N air filters come with a Million Mile Limited Warranty. K&N oiled cotton filter media is protected by a durable, epoxy-coated screen mesh and placed in a custom-poured and cured urethane frame, designed to last for the entire lifetime of your vehicle.

With regular cleaning using K&N’s propriety Recharger Kit™, your K&N filter can be reused time and again, performing virtually like new - which can translate to savings for both you and the environment. Assuming the average engine lifespan is 175,000 miles, you would need to replace approximately 11 paper air filters over the lifetime of your vehicle. With a K&N air filter, you’ll only need one.
Best Engine Air Filter

What are the pros and cons of different kinds of air filters?

It's vital to choose the best engine air filter for your needs.

Disposable paper filters:
Pros: Affordability. In the short term, single-use air filters are the cheapest option. They last for 12-15,000 miles under normal highway driving conditions, which is around a year of use for most drivers. Paper is a fairly efficient filtering medium, and typically blocks contaminants very efficiently, though the tradeoff is typically a reduction in airflow through the filter. That balance of affordability and relative efficiency is why disposable paper filters come standard with most vehicles.
Cons: Airflow. While paper filters perform well when clean, you can expect a steady reduction in airflow as the filter’s pores become clogged with dirt and particulates. At that point, airflow into your engine is increasingly restricted, undermining the performance of your vehicle. As we know, less airflow means less horsepower. For you, that means less acceleration and less muscle as you’re getting on the highway, hauling a heavy load, or traversing hilly or mountainous terrain.

Reusable Air Filters:
Pro: Long-term engine health. Lab tests show most K&N air filters are 97-99% efficient and that they retain their efficiency for up to 100,000 miles depending on the size and shape of the filter. Less dirt and particulates entering your engine often means better engine health, better vehicle performance, and fewer trips to the mechanic.

Pro: Engine performance. K&N’s® High-Flow Air Filter™ allows 50% more clean air into your engine, and its unparalleled balance of airflow and filtration efficiency helps your engine perform at its best.

Pro: Durability. Originally designed for the racetrack, K&N performance air filters have been used in nearly every kind of elite-level motorsport, which gives K&N the confidence to guarantee its filters with a Million Mile Limited Warranty, and stand behind its products with a consumer protection pledge.

Pro: Maintenance. While standard paper filters need to be replaced every 12-15,000 miles, your K&N stock replacement air filter can go up to 50,000 miles before needing to be cleaned (or up to 100,000 miles for the larger conical filters included with K&N intake systems). That said, we do recommend you inspect your engine air filter annually, or more often if you drive in dusty or dirty environments, including high-congestion highways.

Pro: Sustainability and long-term savings. K&N reusable air filters are designed to last for the entire lifespan of your vehicle.

Con: Cleaning. Maintaining your K&N reusable air filter is easy and cost-effective, but it does require a bit of time and the use of K&N cleaning products. You’ll need to remove the air filter from its housing and liberally spray it on both sides with K&N Power Kleen®. Wait ten minutes, then simply rinse off the accumulated dirt until the water runs clear. Use a cold, low-pressure water source (such as a gentle hose or faucet), not a pressure washer or garden hose nozzle. Allow your filter to gently air dry without fans or compressed air. Finally, thoroughly apply a layer of red filter oil and re-install. Cleaning your air filter is an easy, afternoon DIY, requiring very little active time.

For easy-to-follow directions on how to clean K&N® High-Flow Air Filters™, watch this step-by-step video.

How do I find the right reusable air filter?

You’ve decided to invest in a reusable, high-performance engine air filter - now how do you choose the right one for your car?

K&N produces a range of reusable air filters designed to suit the needs and unique fit of your vehicle, as well as your performance ambitions. To find the right fit for your car, truck, motorcycle, or ATV, start your search at You’ll need to know your vehicle make, model, year and engine size to begin. In North America, that information can typically be found on the emissions decal under your hood. The make and model are typically displayed on the rear of your car.

In Europe, your registration documents detail your engine size and vehicle type. If you’re not sure whether your vehicle is single-point injection or multi-point injection, you should consult your vehicle manual or local dealer.

K&N also offers an array of specialty filters designed for industrial use, smaller engines, custom applications, crankcase vents, and high-performance racing environments. If you’re considering a filter for your custom application, you’ll need to factor the shape and size of your air filter. Check K&N’s on-site FAQ under the sub-heading “Finding Products” for your guide to calculating the dimensions of your custom filter.

Click Image to Enlarge

Back to How To Guides.