Replacing a Mass Air Flow Sensor

Written by Doityourself Staff
on Mar 13, 2021

In most vehicles, replacing your mass air flow sensor can be fairly easy. The air tube connecting to the air box is where it is situated. The sensor measures the combustible air that gets to your engine. This is a component that is crucial to a well-run vehicle. Here are a few instructions on replacing the sensor.

Tools and Materials Needed:

Flathead screwdriver
Torx-head screwdrivers
Phillips head screwdrivers
New mass air flow system
Ratchet and sockets

Step 1 - Locating the Engine Air Box

Lift the hood of the vehicle and look for the air box. An air box may look like a box, but it can also look cylindrical. Your car's owner manual will show you the location of the air box. Not all air boxes are in the same area of a vehicle.

Step 2 - Locating the Mass Air Flow Sensor

To locate the sensor, use the one you just bought to find the same thing that is already inside the air tube. The sensor is different in size in different vehicles, but most are connected with an electric plug. Use the flat head screwdriver to unfasten the lock and then unplug the sensor from the harness.

Step 3 - Removing the Air Filter

Opening your air box gives you access to the air filter so you can remove it. All vehicles are different and you may need to use a screwdriver and some vehicles need you to use a Torx-head screwdriver. On some cases it is held closed by metal slides and you don't need a screwdriver at all.

Step 4 - Disassembling the Air Tube

The air tube needs to be disassembled from both sides of the sensor. In almost every application you will only have to release the band clamps using a screwdriver or ratchet and socket.

Step 5 - Removing the Old Mass Air Flow Sensor

This is very simple. You will only have to take the sensor assembly out of the air tube and you are done.

Step 6 - Installing the New Mass Air Flow Sensor

Place the new sensor into the space vacated by the old one in the air tube. Reassemble the side of the air tube to the side that you used to get the mass air flow sensor out. This will allow the attachment of the air tube back into the cover of the air box.

Step 7 - Replacing the Air Tube

Place the air tube inside the air box again. Once the air tube is in, resecure the air tube cover so that the sensor and air tube are protected.

Step 8 - Plugging the Harness into the New Mass Air Flow Sensor

Connect the harness into the sensor outlet . Once done lock it into place with the flat head screwdriver.

Step 9 - Closing and Locking the Air Box to Finish

Now close up the air box and secure it, being sure that everything is connected properly. Your job is now complete and the mass air flow sensor has been replaced.