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When To Replace A Dirty Air Filter

When it comes to proper fuel economy and performance, the proper combustion of fuel is the key. Your engine has various sensors to help it fine-tune the fuel-to-air ratio for maximum combustion. However, if your air filter is clogged up, you will find that your acceleration is far less responsive. It will take full throttle to really get the RPMs up because the engine has to work hard to suck in air through a clogged particulate filter. Having some basic knowledge about air filters and knowing when to change them can save you money and restore the responsiveness of your drivetrain.

When Should I Replace My Filter?

As a general rule, you should replace your disposable air intake filter whenever it looks dirty. A brand-new filter will have a paper material that is either white or cream-colored. If you hold it up to a light and the light does not shine through, this is a good sign that it is due for a change. It is never a good idea to try cleaning a disposable air filter by blowing compressed air through it because this can damage the filter and open up the micropores too wide.

Cleanable air filters can usually be cleaned with oil at every 50,000 miles or sooner if exposed to heavy dust off-roading. A word of caution, however, because the oil used to clean these filters can make some Mass Air Flow (MAF) sensor plates stick in older European vehicles.

You may also notice engine oil staining your air intake filter if it is due for a change. This is a symptom of excessive engine wear and oil blowing past the piston rings. You may want to try switching to a thicker oil weight or rebuilding the engine with new oversized pistons if a thicker oil does not solve the problem.

What Are My Replacement Options?

Most car engine filters are made of paper or foam. The performance air filters are made of cotton gauze layered between wire mesh. A cleanable performance air intake filter is your best choice if you live in a rural area that gets a lot of dusty air. A performance filter can also add a few ponies to your powertrain by simply allowing the engine to breathe better.

If you really want to up the horsepower, add a cold air intake that opens up an expressway to the engine wide and clean. These usually look like thick gauged pipes with cone-shaped filters. Engines operate better when the temperature of the air that they are pulling in is cold because colder air is denser in oxygen and allows for better combustion. If you also add a high-flow exhaust system, you will notice substantial gains in how fast your engine can get up and go.

Where is My Air Filter Located?

The traditional air filters are mounted in a plastic box called an air box. This is usually located on the driver’s side of the vehicle near the battery and connected to the throttle body of the engine with a large hose or plastic ductwork. The air box may have a Mass Air Flow (MAF) sensor mounted on top of it in some European models. It is usually very easy to access the filter by loosening the spring clips on the air box. You can use a flathead screwdriver or even your fingers to lift up on these spring clips and pop the lid off the air box.