A Dirty Engine Air Filter Will Lower Mileage

Engine bay

The engine air filter can have an impact on how smoothly your vehicle drives, as well as your car’s overall fuel efficiency.

If your motor’s air filter is too dirty, it will trap dust and fine particles inside of the engine instead of releasing them back outside. Overtime these dust particles may cause serious damage to the engine’s fuel injection system.

How Air Filters Affect Gas Mileage

Most people don’t think about their vehicle’s lungs – the engine air filtration system. If it’s too clogged up then dirty air maybe entering your engine as dirt. This can cause a host of issues, from decreased performance to increased fuel consumption. The impact will be most notable on your gas mileage.

A dirty air filter can lower your gas mileage by as much as 10% each tank fill-up, depending how bad the filter. While 10% might not seem like a lot in the near term, it sure adds up after a few months, as we’ll demonstrate.

If you drive 15,000 miles per year and don’t change your air filter at least once in that period of time, you’re looking at just over $750 dollars of extra fuel expense on the next 15,000 miles. That’s a significant hit to your wallet, and a problem you can fix yourself.

Why Air Filters Affect Gas Mileage

There are several reasons why changing your air filter can improve your gas mileage. The most obvious one is that a clean filter will allow more air through to your engine, which in turn makes the fuel combust more efficiently.

There are a few other reasons that are worth mentioning.

  • Clogged Air Filters Can Cause Exhaust Gases To Back Up Into The Engine
  • A Clogged Air Filter Can Also Lead To Emission problems

Can you Improve Air Filter Performance

If your air filter is causing any of these issues, it’s worth doing some maintenance on it. You can improve your air filter performance by cleaning it regularly or replacing it when necessary. A good way to clean your air filter is with a car vacuum.

This allows you to remove the majority of the dust without damaging the filter. If your air filter is too dirty, just replace it. They cost an average $25 – $55 USD, depending on the brand and type.

Should You Replace Your Air Filter?

If your air filter is significantly dirty, you should consider changing it. However, if your filter is only mildly dirty, you should leave it alone. With the coming winter months it’s probably a good idea to check the state of your filter, depending on where you live in the US or Canada, this time of year is harder on engines in general.