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Air Flow Meter/Sensor: Description and Operation

Mass Air Flow Meter

Air Flow Meter Assembly:





PURPOSE
The volume air flow meter measures the amount of air being used be the engine. To determine the correct amount of fuel to inject, precise measurement of intake air is necessary.

LOCATION
The sensor is mounted to the air cleaner box on the left side of the engine compartment.

CONSTRUCTION
The unit contains a vane type air flow sensor and an intake air temperature sensor.

OPERATION
An external potentiometer is connected directly to the measuring plate pivot. As the plate deflects due to incoming air, the resistance value of the potentiometer changes. The ECU reads the resistance change by monitoring voltage drop through the sensor.