The Do's and Don'ts of Buying Air Filters

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The Do's and Don'ts of Buying Air Filters

In the same way that crisp, fresh air feels good to the lungs, a clean air filter improves a vehicle's performance because more air can flow in and out of the engine. The general rule is to replace a vehicle's air filter every 12 months or 20,000 kilometres. Going to a mechanic every year can become an expensive endeavour. Fortunately, it is an affordable and fairly simple task to replace the air filter oneself. For those who do not know where to begin when it comes to air filters, following the basic do's and don'ts of buying an air filter can be helpful advice. First, there are different shapes and sizes of air filters and different materials, and the right filter depends on the make of the vehicle.

Consulting the owner's manual and following these tips gives the car owner the wisdom of a mechanic without actually paying for the price of one. Air filters can be purchased in brick and mortar auto parts stores, as well as online through websites like eBay.

The Basic Components of Air Filters

When it comes to air filters, there are two basic components, regardless of the shape, size, or material. A paper-like material filters the air on the way to the engine, and durable rubber ridges hold the filter in place. The air filter can be found in a black plastic case on top of the engine. Depending on the filter's shape, the plastic case is either in the shape of a box or a cylinder.

Filters come in two main shapes: long, elongated rectangles or cylinders. The cylindrical air filter is more common in American-made vehicles and trucks, while the rectangular air filter is the more common type of filter in vehicles overall. Some other less common shapes includering or doughnut-shaped filters and cone-shaped filters.

The most diverse aspect of air filters is the material used in the filtration system. From cotton to foam to polyester, air filters can be found in a wide array of materials.

Filtration Material

Brief Description

Cotton Gauze

Most popular choice for high-performance vehicles; commonly oiled for improved filtration of particles in the air flow; washable and reusable


Most common air filter type; comes on most cars straight from the manufacturer due to cost efficiency; also called 'pleated' on packaging; not reusable


Filter is a simple foam bar or ring; harder to clean between uses

Besides these most common materials, a few filters are available withpolyester,fibreglass,aluminium or stainless steel materials. When buying an air filter, a reliable, efficient material makes a difference on the performance of one's engine. Knowing the different types of air filters that are available for purchase is the first step to making a wise purchasing decision when looking for the right filter for one's car.

Do's and Don'ts of Buying Air Filters

There are different ways to improve the performance of the engine by changing the air filter. When looking for the right air filter to buy, it is important to know the type of filter needed for the specific vehicle. By following the do's and don'ts of buying air filters, car owners can easily purchase a new air filter for the car's engine.

Do Determine the Correct Filter for the Vehicle

Car owners should know the specifications for the proper air filter they need before ever going shopping. Consulting the owner's manual ensures that the correct filter is purchased. If the manual is unavailable, car owners can remove the old air filter and find its match.

If a car has been running, the engine should be left to cool with the hood popped open for several minutes after turning off the vehicle before removing an old air filter. Car owners should also have a standard and a Phillips screwdriver on hand, as well as a knife. The air filter can be found in a black plastic case on top of the engine. The black box should be the largest plastic object in the area. To open the box with the filter, the metal clips that hold the plastic box closed can be slid off using the knife or standard screwdriver. If screws are holding it closed instead of clips, a screwdriver is the alternative solution.

Some cars or trucks have circular air filters, in which case a plastic cylindrical casing should be found on top of the engine, rather than a black plastic box. Opening this second type of air filter case can be done by loosening the wing nut on top of the cylinder.

Do Check the Old Air Filter Before Buying a New One

Car owners should check the level of dirt on the air filter by holding the filter up to the sunlight at arm's length from the face so that the paper ridges are exposed. If there is a lot of dirt accumulated in the centre of the filter, it needs to be replaced.

Don't Assume All Air Filters Are the Same

Air filters obviously have different shapes and sizes for different cars, but there are other differences to consider even after a filter model has been identified. Air filters have two different types of fits,universal and custom. Universal-fit air filters are designed to make the hunt for the right air filter simple for car owners and are available in standard materials for everything from rebuilt classic cars to racing cars. Custom-fit air filters, on the other hand, give car owners the freedom to specify the materials that are used in the design for optimal performance. Upgraded custom air filters provide a different medium to enhance filtering and reduce air blockage to the engine. Shoppers can find air filters that use materials like cotton gauze and foam for filtering finer particles.

There is also a distinct difference between oiled and dry filters. Oiled filters are cotton-based filters that are oiled to help the filter catch more particles from the air going into the engine. These filters are also reusable, as they can simply be washed with a cleaning solution and the filter oil reapplied. Dry filters, on the other hand, do not use oil to catch particles, but the medium used is stronger and is able to catch the smallest particles while increasing the amount of air flow going in and out of the engine. Because the medium is not woven, the dirt shakes off with vibration, which makes the filter low maintenance and longer lasting. Like an oiled filter, a dry filter can be cleaned and reinstalled again and again.

Buying Air Filters on eBay

When looking for the right air filter for one's vehicle, eBay can be an excellent shopping tool. The website offers users a large database from which they can find the perfect air filter for the job by using the search tools on the site. In fact, car owners can use eBay's search features to find air filters that meet both budgetary and material preferences. By inserting keywords like ' cotton gauze air filter' into the search box, all the related products appear on the screen within seconds. Another useful feature that shoppers can use is the eBay Motors site, which helps car owners find items like air filters that match their specific vehicles. Shoppers can use eBay Motors to find the right air filter based on car model and year, and this is yet another way to identify the proper filter for a vehicle.

Customers are always invited to leave feedback regarding all their completed transactions on eBay, and this feedback can be an invaluable tool for potential new buyers. Shoppers should always review a seller's feedback comments before deciding to purchase from that seller.


There are several ways to improve the performance of one's vehicle. The easiest and most affordable way is to change or upgrade the air filter, which is found on top of the engine under the hood. Air filters come in all sorts of shapes, sizes, and filtration materials. The correct type of air filter depends on the specific make and model of one's vehicle, although the material itself can vary and is often chosen on the basis of efficiency and performance. In order to understand which air filter one's vehicle needs, the car owner can either look in the owner's manual or under the hood. Opening the air filter compartment may require the use of a screwdriver to open the plastic casing, and the owner should let the engine cool for a few minutes to prevent injury if it was previously running. Air filters should be changed at least once annually or every 20,000 kilometres, depending on which occurrence happens first.

Various types of air filters can be purchased in local automotive stores and on many retail websites with auto parts, including the mega-store eBay. Regardless of which type of air filter is purchased in the end, a clean air filter means better engine performance so that both the engine and the driver can breathe a little easier.

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