Air Flow Meter/Sensor: Testing and Inspection

INSPECTION

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






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.