|At one point on the Maxima
message boards in late 1999 there was a lot of talk about increasing
airflow through the Maxima intake by removing the screen from the Mass
Airflow (MAF) Sensor. The screen is not a secondary filter as one
might suspect. Its purpose is to "straighten" airflow
going into the throttle body. The theory is that removing the
screen will allow increased airflow and thus, more horsepower.
Being a logically thinking person, the science behind the theory sounded
good to me, and I am willing to give anything a try that sounds
reasonable so.... I removed the screen from the MAF sensor (this process
is irreversible!!) and ran with this mod for almost a full year.
While I did not notice any harmful effects from removing the
screen, I can say for certain that this mod does not increase horsepower
in the slightest, and might possibly even screw up the MAF
readings. Read on.
||For comparison purposes, here are two Mass
Airflow Sensors from a 4th-Generation Maxima. The one on the right
has had the screen removed for (presumably) higher airflow. The
one on the left has the screen intact.
||The way the MAF sensor works is that it
measures the airflow through a very small opening in the center of the
sensor and sends a variable voltage out its electrical connector to the
ECU. The ECU is programmed with the diameter of the sensor and
computes the total airflow into the throttle body based on the flow
through the center section. The reason for the screen is to ensure
that the airflow going into the center portion of the sensor is straight
and smooth so that the ECU's computation will be accurate. If the
flow is not smooth then the ECU computation of total flow through the
barrel will be off. In my opinion, removing the screen will quite
possibly allow a more turbulent airflow through the MAF sensor than
without the screen.
||In spite of my theories as to why the
screen is there and what (I believe) could happen if it is removed, I
still noticed no detrimental effects from removing the screen.
However, since there was also no tangible benefit from this mod I chose
to re-purchase a new MAF sensor and re-install it with the screen in