- In our previous page we showed you how MAF sensors work, how to test them and how to replace them.
In this page you will learn about Airflow meters, and airflow meter works the same way a hot wire MAF sensor does, the difference in their design is that the hot wire airflow meter is mounted in the throttle body housing, while the MAF sensor is mounted in the air intake tube.

The process to test an airflow meter is the same as a hot wire MAF sensor, for more information about how to test a MAF sensor visit our previous page.

 In this page we will concentrate on a Nissan airflow meter, specially because we had the opportunity to diagnose the problem and of course to fix it.


Older Nissan trucks are hard to diagnose even if you own a good scanner, the particular truck we are talking about in this page is a 1988 Nissan pick-up with a 2.4 Liter 4 cyl. Z engine.
The scanner we used in this truck is a Snap-on Solus, but even with this scanner, we were not able to get very far with this truck, because it didn't have any trouble codes stored, and the operating data its engine control computer feeds to the scanner is not the greatest, it doesn't give you any values, it just tells you if there is a fault or not.

Anyway, we have had the opportunity to work on several trucks similar to this one in the past, and we are familiar with their potential problems, this is what this truck was doing:

It was hesitating when taking off , it would cut off at higher speeds with the accelerator all the way to the floor.

We checked the fuel pressure first to make sure that it was not a fuel pump or fuel pressure regulator issue, the fuel pressure was normal, we decided to test the airflow meter, and the readings were inaccurate, it was quite obvious that the airflow meter was malfunctioning.

     

      

      



       

       

      

           

  - As we mentioned earlier, the readings we took from this airflow meter were very erratic, and as soon as we unplugged the electrical connector, we could see a big part of our problem, the connections were corroded, causing an inaccurate reading, and that is just the beginning.

Below are the rest of the steps needed to remove the airflow meter in a Nissan pick-up with a 2.4 Liter Z engine, and the steps to clean it.








  - Remove the three screws that secure the airflow meter to the throttle body housing and remove it from the vehicle









  - We tried to take a close-up picture to show you the corrosion on the airflow meter's hot wire, the picture is very clear , but it does show the color of the wire, it is brown, due to contamination, it shouldn't be that color, any contamination on the airflow meter will cause it to have a bad reading.

 

 

 

  - We sprayed carb cleaner to remove most of the corrosion from the airflow meter.

 

 

 

 

  - The contamination on the airflow meter was so bad that we had to use a soft brush to clean the sensor as we kept spraying it with carb cleaner, we did this several times till it was completely clean.








  - We cleaned the corrosion on the terminals on both sides, the airflow meter and the electrical connector, we installed it back on the truck and took it for a test drive.


 - Huge difference, the truck can do burnouts if we wanted it to, plenty of power, and no hesitation under full throttle, we are happy and so is the owner, another satisfied customer.



         
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