A clean air filter protects the engine from harmful debris without obstructing airflow. To promote engine health, most automotive manufacturers recommend replacing the air filter every 15,000 to 30,000 miles. But, does replacing your car’s air filter also improve gas mileage?

How an Air Filter Affects Fuel Economy

Dirty air filters reduce airflow – Air filters trap contaminants in a media made of paper and synthetic fibers. Over time, this media becomes filled with dirt and debris, preventing the engine from breathing properly. As a result, the engine will work harder and use more fuel.
This affect isn’t as noticeable on modern, fuel injected engines. Late-model vehicles use one or more sensors to measure the amount of air entering the engine. The vehicle’s onboard computer uses this information to adjust engine operation as needed. To some extent, the computer can compensate for a dirty air filter. If, however, the air filter is clogged with dirt, the computer may not be able to.

Clear air filters improve performance and economy – Late-model vehicles aren’t as sensitive to a dirty air filter as older vehicles are, but that doesn’t mean they don’t benefit from air filter replacements. Dense, fresh air always improves engine performance. As a result, you won’t be tempted to stomp on the accelerator as much. This helps improve driving habits for increased fuel economy.

How to Restore Performance and Efficiency

Signs of a dirty air filter – For optimum performance, a dirty air filter should be swapped out. How grimy does the filter need to be to warrant replacement? If the filter looks dirty when held up, and allows very little light to pass through, you need a new one. In most cases, the air filter is pretty easy to access. It’s kept in the air filter housing, which is usually held in place by clips or screws. It’s important to note that a dirty, paper air filter should not be cleaned – it should be replaced.

How to select a replacement air filter – There are a wide range of air filters on the market, some of which perform better than others. For maximum engine performance and efficiency, it’s important to select a high-quality filter. Although they may cost more, good filters provide the best combination of airflow and dirt-trapping ability. For example, Premium Guard air filters are designed to meet or exceed OEM requirements, with 99% efficiency. This means the filters trap almost all air contaminants while also ensuring a low pressure drop for maximum airflow. Both modern and classic engines benefit from this design.

Don’t wait to replace your air filter – Putting off air filter replacement can cost you money at the pump and jeopardize your engine. The best rule of thumb is to exchange your air filter according to the manufacture’s specifications. Replacement intervals can typically be found in your vehicle owner’s manual. Don’t wait until your air filter is black and filthy. Swap it out early on to make your vehicle – and your wallet – happy.