The MY99-00 Subaru Impreza WRX features a unique MAF (Mass Air Flow) sensor, specific to this model year. Unfortunately however this sensor is a common fault item, and often leads to poor engine performance, lean fuel mixtures, and a variety of other issues such as fluctuating idle control or limp mode activation.

We recommend replacing this part if you experience any of the above issues, or if the sensor is more than a few years old. Only purchase a genuine MAF sensor, and cleaning is not recommended.

Difficulty Rating


Tools/Parts Required

  • Genuine Subaru MAF Sensor P/N: 22794AA010
  • Security Torx Driver

Step 1

Firstly locate and disconnect the plug on the MAF Sensor.

You can then unscrew the MAF using a Security Torx Bit. It’s held in place with two screws.

Step 2

For pictorial purposes we’ve removed the upper intake box to show you the rear side of the MAF sensor. Here you can see the two screws.

Step 3

Install the new MAF sensor into position, reconnect and you’re finished.

This simple process is a good starting point for diagnosing engine issues, and can help prolong the life of your motor.

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