What is an engine air filter?
An engine air filter is a paper, foam, stainless steel mesh, oil bath, water bath, or cotton media filter that traps particles from the air before they enter the combustion process of automotive engines. On modern vehicles, paper, foam, and cotton media are the most commonly seen.
The types of particles trapped is everything from dirt and dust from the air, to insects, tree leaves, and anything else that might damage the inner workings of an engine. Air filters can be square, rectangular, round, or cylindrical in shape, depending on the vehicle application.
Why is it important?
Because it traps particles from the air which could potentially damage internal components of the engine, the air filter is a vital part of the air intake system on modern vehicles. Its function also helps prevent the engine oil from becoming contaminated with debris from the air. Both of these heavily contribute to proper running of an engine, and longevity of its internal components.
What can go wrong?
The most common thing to happen to an engine air filter is that it becomes saturated with particles from the air, and needs to be changed. Replacement of this filter is found on every vehicle’s maintenance schedule, usually between every 30,000 and 40,000 miles. Many dusty areas, or areas with lots of pollen in the air will need to increase the frequency of the filter changes because they will become contaminated more quickly. When a filter starts collecting contaminates, it also gradually begins to restrict the air flow going to the engine. Replacement of the filter when needed, or on schedule helps make sure the engine always has the clean air it needs to use in the combustion process.
Another important part of an air filter that can sometimes fail is its sealing surface. In order to ensure that all the air going into the engine gets filtered, air filters have a rubber seal around them that seals against the air intake box. This seal needs to be airtight in order to be effective. The most common reason the seal fails is due to improper installation, but it can also degrade over time if contaminated with automotive fluids, like engine oil.
How do you know if it needs work?
If your vehicle’s maintenance schedule is calling for engine air filter replacement, it should definitely be done. If your vehicle is being serviced at an interval that doesn’t call for engine air filter replacement, most shops will inspect the engine air filter for you to ensure it’s in good shape. In the event that the filter looks dark or black, or there is noticeable buildup of debris in the filter media, it’s a good idea to have it changed.
How much does it cost, and why?
Most engine air filters are fairly simple to access, and change. On some vehicles, it’s so easy that the shop may not charge a labor fee for changing the filter, and just charge for the filter itself. Some vehicles are more difficult to change the air filter, and up to sixty dollars for labor can be normal. Most air filters themselves cost between twenty and sixty dollars, depending on the size and material they are made out of. Some vehicles do use two individual air filters, which both require replacement at the same time, which doubles the cost of parts.