FreightWaves Ratings cuts through the noise of freight technology product reviews to make you a smarter buyer

Does Air Filter Affect Gas Mileage?

Did you know that something as simple as a dirty air filter can noticeably worsen your gas mileage? With rising fuel costs, it’s more important than ever to make sure your vehicle is running in tip-top shape. Meanwhile, trucking companies can save even more money on fuel by using fuel cards for their fleet.

Learn how your air filter can affect your fuel economy, how to tell when it’s time to change your air filter and the benefits of changing your air filters regularly to maximize your vehicle’s performance.

How Do Air Filters Work?

The nature of combustion engines means that they need oxygen to run. Without proper airflow, the engine cannot ignite the fuel that powers the engine. In addition, engines are sensitive to dust, dirt, bugs, and other particles in the air. 

To provide clean air to the engine, you need an air filter to prevent contaminants from entering the engine and causing performance issues and damage. Air filters allow the necessary ventilation required to run the engine by only allowing clean, particle-free air through. 

How Does an Air Filter Affect Fuel Economy?

Since your vehicle’s engine needs a steady flow of clean air to operate at its best, it needs a clean air filter that blocks harmful debris from reaching the engine while still allowing full ventilation. As a result, your engine will not strain to burn the gas, necessitating less fuel. 

Dirty Filters

Dirty air filters reduce airflow, which is needed for smooth engine operation. Over time, the build-up of dust and particles in your air filter blocks this airflow necessary for the effective combustion of fuel in the engine. This reduces your engine’s efficiency, worsening your fuel economy. 

Clean Filters

In contrast, a clean air filter improves engine performance and fuel economy by allowing steady airflow to reach the engine. Clean air filters also are better at blocking harmful particles from entering the engine. 

Due to their advanced filters, newer, late-model vehicles are less sensitive to the worsening fuel economy issue. However, a dirty air filter can still impact your fuel efficiency over time, regardless of your vehicle’s model year. 

Will a Bad Air Filter Cause Bad Gas Mileage?

Inadequate air filters and bad oxygen sensors can reduce your gas mileage by up to 20%. Conversely, replacing dirty air filters and regularly checking your oxygen sensors can significantly improve fuel efficiency. 

However, a dirty air filter is not the only culprit of pool fuel economy. For trucking companies looking to maximize their fleet’s fuel efficiency, fuel management systems monitor everything from fuel consumption to idling. 

What are the Signs of Dirty Air Filters?

Replacing dirty air filters is essential for keeping your vehicle operating at its best. Luckily, a few signs can alert you that it’s time to change your air filter. 

  • The air filter visually appears dirty
  • The check engine light comes on
  • Engine misfires or misses when starting
  • Strange engine noises
  • Reduction in horsepower  
  • Black smoke or flames from the exhaust pipe
  • Strong fuel smell
  • Worsening fuel mileage

What Happens if I Don’t Change My Air Filter?

Not changing your air filter in the short run causes performance issues quickly. Your vehicle will likely experience worse fuel economy since less air will reach the engine to combust the fuel. However, you can have other issues such as increased harmful emissions, loss of power, and trouble starting. 

Never changing your air filter can make your engine stop running if it doesn’t receive enough oxygen to run. In serious cases, your engine can work so hard to pull clean air through the filter that particles can enter the engine causing permanent damage. 

5 Benefits of Changing Your Air Filters

Changing your air filters is an inexpensive and straightforward maintenance task important for every vehicle owner for its many benefits. 

Increased Fuel Efficiency

Changing your air filters can increase your fuel economy. When your engine receives the oxygen it needs to combust fuel efficiently, it requires less gas to provide the same power. A clean air filter allows for the necessary level of airflow for this efficient fuel combustion. 

Reduced Emissions

Replacing your air filters is better for you, your vehicle, and the environment. Clean air filters aid the emissions system in your vehicle by allowing proper airflow, while a dirty filter prevents the emissions system from working at full capacity. 

Prolonging Engine Life

Keeping up on air filter replacements is an essential part of engine maintenance. Over time, your engine would need to work harder and harder to pull air through a dirty filter. This can eventually introduce the very particles it’s filtering into your engine. By taking care of your engine, you can prolong its working life. 

Inexpensive and Easy 

Air filter changes are one of the most straightforward car maintenance tasks but make a big difference in engine performance. It only takes ten minutes to replace most air filters, and a new air filter will run you less than one hundred dollars with installation. Whether you do it yourself or have your mechanic include it on your next tune-up, air filter changes are inexpensive and they add great value to your vehicle.

Simple To Track

Tracking when you need to change your air filters is simple. Every 12,000 to 15,000 miles, you should be changing your air filters, more often if you drive in dusty or industrial environments. Check your manufacturer’s recommendations for air filter replacements in your owner’s manual for vehicle-specific guidelines. 

Improve Your Fuel Efficiency with an Air Filter Replacement

Replacing your air filter is a quick and easy solution that improves your gas mileage and your engine’s performance. So, if you feel like it’s been a while since you last replaced your air filter, give it a look or check your maintenance records. 

With high gas prices, every last mile counts! For even more insights into the transportation industry, be sure to subscribe to the FreightWaves e-newsletter. 

Zero-fee fuel card – accepted everywhere!

NO monthly service fees, NO credit score or SSN required, universal discounts, and a driver-friendly dashboard!

Zero-fee fuel card – accepted everywhere!

NO monthly service fees, NO credit score or SSN required, universal discounts, and a driver-friendly dashboard!