Engine air filters are a necessity for your vehicle. All internal combustion engines need air to run, and engine air filters let air into the engine while keeping out dirt, dust, and other particulate matter. Like all other air filters, they get dirty and need replacing every now and then. A dirty air filter can cause all kinds of symptoms. The biggest, and perhaps most important, symptom of a dirty filter is changing the air-fuel balance in your car’s engine which can lead to reduced output. Thus, it’s important to change your air filter regularly.
Luckily, air filters are not high-maintenance items. The general wisdom is to change your engine air filter about every 12,000 to 20,000 miles, or about once a year depending on who you ask. That’s less often than changing your motor oil, but more often than changing your spark plugs. These are also relatively inexpensive, with most brands going for under $30. You can pick one up on Amazon and install it yourself with the help of a YouTube video. It’s reasonably easy to do and it’ll save you a few bucks versus going to a dealership.
From there, it comes down to choice, and there is a give and take when it comes to air filters. Generally speaking, an air filter that traps more dust and particulates also reduces airflow as a function of being thicker. Meanwhile, performance air filters do the bare minimum in terms of filtering, but they tend to let more air through for the sake of higher performance. Most air filters fall somewhere in the middle, but you can find filters on either end of the spectrum.
Bosch
Bosch only makes one engine air filter. It’s called Workshop, and despite its name, it is for a car and not a workshop. These filters vary in size, shape, and style depending on the make and model of your vehicle. There are even round filter variants for cars that use round air filters instead of flat ones. It boasts wide support for U.S. domestic, Asian, and European cars. However, Bosch does not make air filters for every vehicle.
What makes Bosch an interesting choice is how cheap the filters are. You can typically find them for about $10, and sometimes even less. This makes it a good, cheap option if you need an air filter on an extremely tight budget. Bosch’s large selection typically means you can find one in your car’s size or shape. The mix of availability and budget can make Bosch a decent option, even if its performance is fairly middle-of-the-road.
Most online retailers such as Walmart, Amazon, and eBay have Bosch air filters available. All three retailers have more or less the same inventory, so it’s just a matter of figuring out which version of the filter you need. Bosch’s official website has a vehicle compatibility tool so you see if the company makes a filter your car can use and which part number it is.
EPAuto
EPAuto is good for many of the same reasons as Bosch. It’s widely available, not terribly expensive, and there are plenty of options for a lot of different vehicles. A lot of EPAuto’s products are geared toward older cars, so those looking for an engine air filter on a 2007 Subaru Outback will likely run into EPAuto’s products more frequently than someone with a 2023 Subaru Outback, for example. Of course, there are modern options too, but it’s nice to see EPAuto supporting older vehicles as well as it does.
In terms of performance, EPAuto is fairly run-of-the-mill. It competes favorably with brands like Fram and ACDelco, so you can expect similar performance to those other brands. It lets in enough air and filters out enough particulate matter to where you can purchase one, install it, and feel okay about your decision. There isn’t much that helps EPAuto stand out from the pack, but that’s not necessarily a bad thing. These air filters just work fine, and sometimes that’s all you need.
In general, you can find these filters in a variety of places. The usual online retailers are typically your best bet. It’s the same routine as most other air filters in that you typically find one that matches your car and then install it. EPAuto’s filters last for about 12,000 miles according to the product’s packaging, so it’s on the lower end when it comes to longevity.
Ecogard
Ecogard is a good overall engine air filter brand. It’s on the same level as Bosch or EPAuto, where you’re getting a cheaper product that still works relatively well. You can find these for less than $10 for many vehicles, and they work just about as well as more expensive filters. You’ll get reasonably good filtration along with reasonably good airflow. It doesn’t tend to do better in one area than another, so it’s one of those situations where it’s a safe bet, but you’re not getting any extra performance or amazing filtration.
Ecogard is among the best when it comes to budget brands. The company seems to make filters for a ton of vehicles. It specifically touts having over 500 SKUs supported, which is quite a lot. This includes rigid, round, and flat panel air filters. There is also a helpful tool on the official website to see if Ecogard has filters for your model specifically. There aren’t a lot of complaints out there with Ecogard filters, and that’s because they work well.
In terms of availability, online retailers are the way to go. Amazon is a pretty good starting point if you want to search for Ecogard filters thanks to its ability to match parts with your car. In fact, it worked better than Ecogard’s tool when it came to finding filters. In any case, you’ll find it cheaper online than you will in brick-and-mortar stores, so it’s a good place to start.
Purlator
Purolator is a pretty big name in air filters. The company not only makes engine air filters but also cabin and furnace air filters in a variety of styles. The company even does oil filters and is one of the most popular brands, comparing favorably with the likes of Fram, ACDelco, and others. As one of the bigger names, there is support for tons of vehicles both new and old. There’s a Purolator filter for almost any occasion. For car engines, you’ll want to look for the PurolatorONE branding since those are specific to vehicles.
Purolator filters test quite well. The company offers a high amount of efficiency while also filtering the air better than most cheaper brands. Thus, you get a good mix of air into the engine while also keeping out most of the dirt. In several tests, PurolatorONE filters do about as well as WIX and ACDelco brands, so you can really choose any of these brands. PurolatorONE excels at being a well-balanced filter. It lets in plenty of air, but also filters out plenty of dirt. However, that means it doesn’t excel at either one, which is generally okay for normal car use.
You can find PurolatorONE filters almost anywhere. Online retailers are obviously the easiest option, but you can typically find these in physical locations like Advanced Auto Parts. Wide availability mixed with good performance makes PurolatorONE a solid overall choice for most types of vehicles. However, performance-oriented cars may want something a bit thinner to give the engine more air.
ACDelco
ACDelco is a subsidiary of General Motors (GM). One of the interesting side products of that relationship is that ACDelco supplies GM with air filters as OEM (original equipment manufacturer) parts. As a result, ACDelco is about as good as an OEM air filter. We’ll get more into why that’s not necessarily a bad thing later, but for now, let’s discuss more about ACDelco in general. The company makes engine air filters for plenty of vehicles, and not just for GM. The only downside is that the list of supported non-GM vehicles is fairly short.
In terms of performance, ACDelco is roughly equivalent to Purolator. It offers a good mix of airflow and filtering power. However, it does tend to lean to the side of filtering. That means there’s more air resistance, while filtering more particulates. It’s not nearly enough to affect the performance of a daily driver, though folks looking for performance-oriented filters may want to look elsewhere. Otherwise, it’s a solid filter that works quite well and it should easily go for the 12,000 miles recommended between air filter changes.
Shopping for ACDelco is a tad tricky. Amazon is probably the best place to start with its vehicle matching function. Usually, other sites like Walmart work pretty well, but they may not have as large of a selection. Auto Zone also carries ACDelco air filters in case you want to buy one in person. Overall, these are solid filters for an average price.
Fram
Almost everybody has heard of Fram. The company makes filters for nearly everything from cars to furnaces and even oil filters. The brand has been around for almost a century, so its foothold in the market is seemingly ironclad.
In terms of performance, Fram is the opposite of ACDelco. It tends to let a little more dirt through, but also allows more air through. Again, this doesn’t matter much for average, daily driver cars. Your engine isn’t going to suddenly get massively dirty and break because you went with Fram over ACDelco. However, OEM air filters also tend to let more air through, so Fram is a bit closer to what one would expect from an OEM filter, depending on the OEM. That’s not a bad thing by any stretch.
You can purchase Fram products almost anywhere, which is part of what makes the brand appealing. These filters can be found at Walmart, almost all auto parts stores, and online. Fram tends to be a bit more expensive than other brands, but not horrifically so. You also likely won’t have any trouble finding an air filter for your vehicle thanks to Fram’s excellent support for a wide range of vehicles. STP is an alternative to Fram in that it’s also available everywhere.
K&N
K&N is a performance brand that makes high-flow air filters and is a fairly well-known brand in the performance segment. K&N air filters are unique compared to most filters. They are oiled, which means it’s a wet filter and not a dry filter. In addition, the filters are washable and reusable. That means a single filter lasts much longer than a regular paper filter, which explains its higher-than-average price tag. Once you clean it, you have to reapply the oil. K&N sells kits that contain cleaner along with the proper oil. While this adds to the price, it also takes out the guesswork.
K&N filters, as the high-flow descriptor suggests, are adept at letting in tons of air. There aren’t many air filters that let in this much air, so that makes it excellent for performance purposes. However, that production comes at the cost of filtering efficiency. K&N filters routinely score low on filter tests. We’re not just talking about slightly lower-than-paper filters. It’s by a fairly significant margin. Plus, the oil on it collects dirt rather quickly, so you will likely need to clean this filter a lot more often than you would replace a paper filter.
K&N has several competitors in this space, and those brands are all reasonably good for various reasons. AEM, which we’ll discuss later, has a dry washable filter that’s a little easier to maintain, but K&N still lets more air through. These are purpose-built filters and they’re not recommended unless you’re applying them to a performance car.
AEM
AEM is an aftermarket car parts company that specializes in performance-oriented parts. The company’s air filters are interesting because they are washable and reusable. This means they’re a fair bit more expensive than the paper filters that populate this list, but the ability to use them multiple times means you don’t have to buy a new one for at least a while if you take proper care of it. It boasts 50,000 miles of highway driving before it needs cleaning. That’s a lot longer than most other air filters.
AEM’s quality makes it a legitimate brand in the space. The construction quality of these air filters is above what you would typically find in an engine air filter. That’s likely due to the fact that you can reuse them so many times, so they need to be robust enough to live that long. Testing shows that AEM filters have an efficiency of between 98.4% and 99.4% when it comes to filtering out pollutants, which is an excellent result. It also lets in enough air to where you can goose a little extra performance out of your performance car if you have one.
AEM and K&N trade blows in this space. K&N is an oiled filter whereas the AEM is a dry filter. They are both reusable, washable, and let in a bunch of air. K&N seems to be better at letting in air, but it’s worse at actual filtering. You can go either way with your decision here as it mostly comes down to preference.
WIX
WIX makes excellent air filters. The company also does oil and cabin air filters as well, so you can get all of your filtering needs from a single place. WIX even makes filters for large vehicles like heavy trucks, buses, and off-road vehicles. That said, this is not a performance brand by any stretch. The brand makes typical paper filters which is what most air filter brands do. This doesn’t WIX a bad brand, but performance-oriented folks should scroll back up to the AEM or K&N sections.
In terms of performance, WIX is a middle-of-the-road performer. The filters eat up a lot of dust while still giving you a good amount of airflow; a difficult result to find from other manufacturers. ACDelco has very strong filtering, but this has the consequence of less airflow. Fram lets in more air, but filters less dirt. WIX sits right in the middle of both of them. The brand uses a no-compromises approach that pulls from the best of both worlds. However, folks who prefer more filtration or more airflow may still want to go with another brand.
WIX is generally available in the same spots as the other air filters. We recommend checking Amazon so you can include your car to ensure proper fitment. They’re a little harder to find in physical stores, however, so if you’re wanting to pick one up personally, you’ll likely need to look elsewhere. WIX filters also tend to be more expensive than the budget brands, but are still usually less expensive than OEM.
OEM
A lot of folks land on lists like these to get away from OEM air filters. Here’s the thing: OEM’s filters aren’t that bad. Independent testing has shown that OEM filters aren’t all that restrictive, so they allow for adequate air to make it into your engine. In fact, OEM filters are designed specifically for your car’s engine and ensure that the right amount of air is getting into it. This makes the company’s products an easy, low-impact choice when replacing your air filter.
In addition, OEM filters are above average at filtering out particulates. You will also get the benefit of perfect fitment since you are replacing the part with an identical part. Third-party air filters aren’t bad enough that it’s an issue, but there’s a level of comfort in knowing that your air filter is the exact one that fits in your car. Of course, the automaker that made your car may recommend you go with an OEM filter mostly for these reasons.
OEM filters have the added benefit of being generally cheap assuming you buy them from a supplier and not from the dealership. Many folks get them from dealerships, which can inflate costs, and the dealership charges quite a bit to install them as well. Using dealerships can make OEM filters the most expensive option. If it helps, many car manufacturers farm OEM parts out to brands like Fram and ACDelco anyway, so these filters are not demonstrably different from other filters on the list.
