The Maxima MAF Sensor in your 3.5 liter engine is a big part of your Nissan EFI system. The MAF is also known as the mass air flow meter, and it’s mounted inline of your intake tract. It’s mounted there to read the incoming air charge to your VQ35 engine, and read information about the air. The Maxima MAF sensor then converts these readings into voltage readings that your Nissan computer can use.
Your 3.5 liter Nissan engine uses this information to deliver the right fuel adjustments. If your mass air flow meter encounters issues or becomes fouled, you’ll see just how important this sensor is. When the VQ35 MAF sensor starts going bad, you’re Maxima will suffer from poor idle characteristics and run poorly. Today I’ll be showing you how to test a mass air flow meter in a 2008 Maxima with a 3.5 liter Nissan engine in it.
Because your Maxima MAF sensor uses an integrated intake air temperature sensor, some of the Nissan Maxima symptoms can be hard to diagnose. Some of the more common Maxima issues also stem around engine idle and the air fuel ratio of your 3.5 liter engine.
Common Nissan issues from a bad Maxima MAF Sensor
Failed mass air flow meters can cause Maxima problems that are commonly misdiagnosed. Because the majority of these issues center around the air fuel mixture in your combustion chamber, these can be hard to track down. Here’s a few of the common Maxima issues below;
- Poor gas mileage
- Bad performance
- Erratic engine idle
- Check Engine Light ON
If you have any of these symptoms you are best served by using this How To guide to test your Maxima air flow meter. To do this however you will need a digital multimeter to test the circuits and wires at each terminal.
Testing your Maxima MAF for Power
The first order of business is to open your Nissan hood and locate your air flow meter. It’s bolted to your air box by four 10mm bolts. Once you’ve found this unit, depress the wiring connector tab and disconnect it.
Testing for power at this MAF connector is easy to do once you turn the ignition to the “ON” position. Now gently probe the female side of the ENGINE harness at PIN 2 using the wiring diagram below.
With the red lead of your multimeter at PIN 2 on the ENGINE side of the harness, you should have a switched power signal.
If you have power here the next wire to check is PIN 3 of our Maxima MAF wiring diagram. There should be a ground signal present at this wire, and if you don’t then this is a big problem. This low reference signal is sent by your ECU, so if there’s no ground here you will need to check for continuity between PIN 3 and ECU terminal 67 of your Nissan computer.
Now if you have power and ground at your karman style air flow meter, the next order of business is to measure the Maxima MAF signal. The signal wire is located on PIN 4 in the diagram above, or WIRE 3 of the Maxima MAF schematic below.
To test this part of our DIY tutorial, you’ll need to reconnect the mass air flow sensor.
Now with the MAF reconnected, pierce WIRE 3 using the diagram to the left. This wire should be the MAF signal wire.
Keep your hands and tools clear of your engine bay and your cooling fans. Leave your ignition turned to the “ON” position, but do not start your engine yet.
With the ignition switch ON you should have between 0.4 – 0.6 volts of Maxima MAF signal. Now start your 3.5 liter engine and allow it to warm up. Once it’s warmed up this signal wire should transmit between 1.0 – 1.2 volts of power.
Now increase engine speed to 2,500 RPM and measure the signal. Your Nissan air flow meter should be transmitting between 1.0 – 1.2 volts of signal. The last step is to raise or increase RPM to 4,000 RPM at which point the MAF should increase between 1.6 – 2.0 volts of signal.
If your Maxima MAF sensor does not respond in this manner, chances are it’s gone bad. You’ll need a replacement Nissan air flow meter before you remove the bad one.
Replacing your Maxima MAF Sensor
Before you can clear your Nissan Maxima check engine light, you’ll need to replace the air flow meter. Begin by loosening the 10mm bolts that hold the Maxima mass air flow meter to your airbox.
Now loosen the worm clamps on your intake snorkel that leads to your Nissan throttle body. The snorkel should lift up in one piece along with your MAF sensor. Inspect your air snorkel for any leaks or cracks, that can also have an adverse effect on how your MAF sensor operates. Once you’ve replaced the MAF sensor, use a OBDII scan tool to clear your Maxima check engine light.
Have any questions about how to test a Maxima MAF Sensor? Leave them for us below!
