How Air Filters Improve Gas Mileage

I’m sure most of you know that Air and Fuel are mixed together to be burned in your engine. The amount of which is determined by how hard you press on the accelerator, by going up or down a hill, or by the load you are carrying as you drive around the Indianapolis, Castleton or Fishers area. Based on how much air you request, your engine computer will control the amount of needed fuel to your engine. But what if the computer gets the wrong details about how much air is coming into your engine? When this happens the engine computer will send the wrong amount of fuel to the injectors and there goes the fuel economy and performance.

The Mass Air Flow (MAF) Sensor is a critical sensor that is used to measure the volume, temperature, and density of the air coming into your engine. It’s usually mounted in the air intake system before the throttle body but after the air filter. The computer will calculate how much oxygen is available to burn and adjusts the amount of fuel it will send to the injectors. If you have a a dirty or damaged MAF sensor, the engines computer will get inaccurate information to calculate fuel demand, which can lead to a poor running engine, damage to your catalytic converter, set off the Check Engine Light, and may even prevent the engine from running.

When air first enters, it first passes through the engine air filter. All the nasty stuff in the air gets trapped in the air filter. At least until you let the air filter go too long and it gets too clogged. At this point some of the contaminants will pass through the filter and hit the MAF sensor. That is how the sensor gets so dirty that it cannot accurately measure the amount of air coming into the engine. So the next time your service adviser brings out a dirty air filter to show you and asks if you’d like to replace it, it’s for your own money saving benefit.

If your MAF does become contaminated, most of the time it can be cleaned. The best way to do this is to perform a Fuel Tune. This service also cleans your throttle body and other fuel system components. In the circumstances where the MAF sensor has been damaged, it will need to be replaced.

It takes about 12,000 gallons of air for every gallon of fuel that you use. That’s a lot of air to have your air filter clean. As you can see replacing this inexpensive part is a good investment. It will prevent dirt from getting into your engine, it will help keep your MAF sensor working the way it should. A good quality engine air filter is your engine’s first line of defense.

When your friendly Professional Automotive Service Adviser recommends you replace your engine air filter, consider how much money you will save in engine performance.

At Professional Automotive in Indianapolis IN (46250) we install quality NAPA replacement parts. Give us a call at 317.596.0898. To learn more about NAPA AutoCare, visit

air filters improve gas mileage