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Air Flow Meter/Sensor: Description and Operation

(Volume) Air Flow Meter:






A Bosch vane type airflow meter is mounted in the air induction system near the air cleaner. The airflow meter measures intake air volume, and converts these readings into voltage signals by means of a variable resistor (potentiometer). These voltage signals are then sent to the ECU and used to determine injection duration and proper fuel delivery. When intake air volume is low, the voltage is high; when the intake air volume is high, the voltage signal is approximately zero.