How to Replace a Mass Air Flow Sensor

by Jody L. Campbell

In most automobiles and trucks, having to replace the mass air flow (MAF) sensor can be as easy or difficult as replacing the engine air filter. The MAF sensor is placed in the air tube that runs from the air box, where the filter is located, to the engine. It measures the amount of combustible air getting to the engine and it is a crucial component for a well running engine. When replacing a MAF sensor, you might consider replacing the air filter as well.

Open the hood to your vehicle and locate the engine air box. Check your owners manual for the location of the air box. In some vehicles, it can look boxy, in others, it may be cylindrical. Vehicle manufacturers do not always place the air box in the same location.

Locate the MAF sensor by opening the box that the new one came in and finding the same component inserted into the air tube running from the air box to the engine. The sensor comes in a variety of shapes and sizes depending on the vehicle, but most have an electrical plug the connects directly to them. Use the flathead screwdriver to release the lock and unplug the harness from the MAF sensor.

Open the air box and remove the air filter. On some vehicles, various screwdrivers may be needed including in some applications the use of a torx head screwdriver. Some air boxes have metal clips that require no tools and can be opened with the flick of a finger.

Disassemble the air tube on either side of the MAF sensor. In most applications there are band clamps present that can be loosened with a Phillips head screwdriver or a ratchet and socket.

Remove the old MAF sensor from the air tube assembly.

Install the new MAF sensor to the air tube and reassemble the tubes to either side of it. This will attach the air tube back to the air box cover.

Insert the new air filter into the air box and re-secure the cover.

Plug the harness back into the new MAF sensor outlet.

Tip

  • check In most cases, when a MAF sensor goes bad, it will trip a check engine light on the vehicle. This was most likely already diagnosed by a service station or parts store with a code reader. Communicate with the parts store or station to see if they'd be willing to clear the code once the MAF sensor has been replaced. Also, be careful when handling the new MAF sensor and avoid touching the interior element of it with your fingers or getting any contaminants on it.

Warning

  • close Be careful when handling the new MAF sensor and avoid touching the interior element of it with your fingers or getting any contaminants on it.

Items you will need

About the Author

Jody L. Campbell spent over 15 years as both a manager and an under-car specialist in the automotive repair industry. Prior to that, he managed two different restaurants for over 15 years. Campbell began his professional writing career in 2004 with the publication of his first book.