The Xterra MAF sensor is found in the intake tract, and it’s there to monitor your air flow. As your Nissan truck is running, air that enters into your engine or supercharger is analyzed by the Xterra MAF sensor. The MAF is also called the mass air flow meter, and its primary role is to provide your Nissan engine computer with the information needed to operate your engine.
Today I’ll be showing you how to test the Xterra MAF sensor in a 2002 Nissan truck with a 3.3 liter engine in it. This DIY guide requires that you have a digital multimeter to test your mass air flow meter, and the circuits at the wiring harness.
When your Xterra MAF sensor starts to go bad, you’ll notice a few common Nissan Xterra issues. These problems can cause issues with your engine idle, and cause a lack of power and poor gas mileage to name a few symptoms. Of course one of the earliest warning signs that your Xterra MAF sensor is going out is when you notice your Nissan Xterra check engine light on.
Before you can test your Xterra MAF sensor, you will need to locate it. The Nissan MAF in your 3.3 liter truck is mounted to the air intake box and connected to your intake tract. Once you locate the mass air flow sensor, disconnect it and you are ready to begin testing.
Testing your Xterra MAF Sensor for Power
Using your digital multimeter, you can test the power wire at the MAF connector. This is found at PIN 1 in our Nissan MAF wiring diagram. To test for power here however, you need to turn the Xterra ignition to the ON position.
With your key turned to the ON position, you should have around 12 volts of power here. Remember that you are testing on the ENGINE harness side of the Xterra MAF sensor.
This wire is usually black with a yellow wire, although it may vary depending on your vehicle.
If you have power here the next wire to check on is the ground circuit. This is located at PIN 2. Testing this wire should be done through your Nissan battery and never through your wiring harness. To be clear, do not use the power wire at PIN 1 for power to check for a ground circuit at PIN 2.
Now if you have a ground circuit at the wire of PIN 2, then the last leg of this DIY article is to check for the Xterra MAF sensor signal.
Before you begin testing the Xterra MAF sensor signal, you would be best served with a notepad and a pencil to record your base values. The MAF signal wire is the one that leads to PIN 3, and you will need to reconnect the MAF connector for this part of the test.
Once you have the Xterra MAF sensor reconnected, you must use your multimeter and pierce the wire at PIN 3. For this part of the test, you will need to start your 3.3 liter engine. This means that you must steer clear of the engine, cooling fans as well as any moving parts and keep your tools clear as well.
Have a friend start your Xterra, but make sure your parking brake is on and your transmission is in PARK or NEUTRAL. With the engine idling, read the signal wire at the mass air flow sensor and you should see between .9 to 1.6 volts. Now you can have your friend raise the engine speed to 2500 RPM, which should raise the Xterra MAF sensor signal between 1.7 to 2.3 Volts DC.
Allow the engine speed to fall back to idle, and monitor the signal wire. The voltage should sweep downward smoothly without any spikes or missing voltages.
If your Xterra MAF sensor returns no value or signal, or does not respond in the ways we’ve outlined your mass air flow sensor has gone bad. Remove your bad MAF and install a new replacement unit, and use the OBDII scan tool to erase any stored DTC trouble codes.
Have any more questions about your Nissan Xterra MAF Sensor? Leave us a comment below and let us know!