200SX L4-1998cc 2.0L DOHC MFI (SR20DE) (1995)
Mass Air Flow Sensor: Description and Operation
MASS AIR FLOW SENSOR (MAFS) (DTC: P0100)
The mass air flow sensor is placed in the stream of intake air. It measures the intake flow rate by measuring a part of the entire intake flow. It
consists of a hot wire that is supplied with electric current from the Engine Control Module (ECM). The temperature of the hot wire is con- trolled
by the ECM a certain amount. The heat generated by the hot wire is reduced as the intake air flows around it. The more air, the greater the heat
loss.
Therefore, the ECM must supply more electric current to maintain the temperature of the hot wire as air flow increases. The ECM detects the air
flow by means of this current change.