FUNCTION
AND OPERATION PRINCIPLE
Mass Air Flow Sensor
(MAFS) is a hot-film type sensor and is located in between the air cleaner
and the throttle body. It consists of a tube, a sensor assembly and honey
cell and detects intake air quantity flowing into the intake manifold.
While the intake air coming out of the air cleaner flows by the honey
cell, it becomes laminar flow, and then it passes the hot-film. At this
time, heat transfer is generated by convection and this sensor loses its
energy. This sensor detects the mass air flow by using the energy loss and
transfers the information to the PCM by frequency. The PCM calculates fuel
quantity and ignition timing.

SPECIFICATION
Air Flow
(kg/h)
|
Output Frequency
(Hz)
|
12.6
|
2,617
|
18.0
|
2,958
|
23.4
|
3,241
|
32.4
|
3,653
|
43.2
|
4,024
|
57.6
|
4,399
|
72.0
|
4,704
|
108.0
|
5,329
|
144.0
|
5,897
|
198.0
|
6,553
|
270.0
|
7,240
|
360.0
|
7,957
|
486.0
|
8,738
|
666.0
|
9,644
|
900.0
|
10,590
|
SCHEMATIC
DIAGRAM

COMPONENT
INSPECTION
1. |
Check the MAFS visually.
A. |
Mounting direction
correct. |
B. |
Any contamination, corrosion or damage
on connector. |
C. |
Air cleaner's clogging or
wet. |
D. |
MAFS cylinder's deforming or blocking
by any foreign
material. | |
2. |
Check any leakage on intake system and
intercooler
system. |