engine
Mass Air Flow Sensor
for 2021 Ford F-150 3.5L V6 EcoBoost · 4WD
Difficulty
Easy
Time
24 min
Tools
4
Steps
9
This procedure covers the removal and replacement of the Mass Air Flow (MAF) sensor on the 2021-2024 Ford F-150 3.5L V6 EcoBoost engine.
Warnings
⚠Do not touch the sensing element inside the MAF sensor housing as oils from skin can damage the delicate sensor wire.
ℹ️Ensure engine is cold and key is in the OFF position before beginning work.
Tools required
Torx T20 screwdriver or bitEssential
Flathead screwdriver (small)
Torque wrench (inch-lb range)Essential
Clean microfiber cloth
Parts
- Mass Air Flow Sensor × 1 — Motorcraft DY1254 or equivalent OEM
Preparation
- Park vehicle on level ground and turn off the ignition
- Allow engine to cool if recently operated
- Open hood and secure with prop rod
Procedure
- 1Locate the MAF sensorThe MAF sensor is located in the intake air tube between the air filter box and the turbocharger inlet. It is positioned on the passenger side of the engine bay, integrated into the air intake tube approximately 6-8 inches downstream from the air filter housing.
- 2Disconnect the electrical connectorPress down on the red locking tab on the MAF sensor electrical connector and pull the connector straight away from the sensor. If the connector is difficult to remove, gently wiggle it while pulling. Do not use excessive force.
- 3Remove the MAF sensor mounting screwsUsing the Torx T20 driver, remove the two screws securing the MAF sensor to the air intake tube. These screws are located on opposite sides of the sensor housing. Keep screws in a safe location for reinstallation.Torque specMAF Sensor Screws3 Nm (2 lb-ft)
- 4Remove the MAF sensorCarefully pull the MAF sensor straight out of the air intake tube. The sensor may be seated with an O-ring seal that provides slight resistance. Avoid twisting or tilting the sensor excessively during removal.
- 5Inspect the air intake tubeCheck the inside of the air intake tube for dirt, debris, or oil contamination. If present, clean with a clean microfiber cloth. Inspect the O-ring groove in the tube for damage or debris and clean if necessary.
- 6Prepare the new MAF sensorRemove the new MAF sensor from its packaging. Verify that the rubber O-ring seal is properly seated in the groove on the sensor body. Do not apply any lubricants to the O-ring or sensor.
- 7Install the new MAF sensorAlign the new MAF sensor with the opening in the air intake tube, ensuring proper orientation by matching the screw holes. Insert the sensor straight into the tube until it seats completely against the tube housing. The sensor should sit flush with the tube surface.
- 8Install and torque the MAF sensor screwsInstall the two Torx T20 screws by hand until they are snug. Using the torque wrench, tighten the screws to specification in a cross pattern (alternating between screws). Do not overtighten as this can crack the sensor housing.Torque specMAF Sensor Screws3 Nm (2 lb-ft)
- 9Reconnect the electrical connectorAlign the electrical connector with the MAF sensor terminal and push straight on until you hear and feel a distinct click. Verify the red locking tab is fully engaged. Gently tug on the connector to confirm it is secure.
Reassembly
- Ensure all electrical connections are secure and locked
- Verify MAF sensor screws are torqued to specification and sensor is seated properly
Verification
- Start the engine and verify it runs smoothly without rough idle or check engine light
- Allow engine to idle for 2-3 minutes and monitor for any unusual operation
- Test drive the vehicle to confirm normal acceleration and throttle response
- Use an OBD-II scanner to verify no MAF-related diagnostic trouble codes are present