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Air Flow Meter/Sensor: Description and Operation




MASS AIR FLOW SENSOR (MAF SENSOR)
This hot film type air flow sensor is composed of a hot film sensor, housing, and a metering duct (hybrid, sensor element). The mass airflow rate is measured by detection of heat transfer from a hot film probe. A change in the mass air flow rate will cause a change in the amount of heat being transferred from the hot film probe surface to the air flow. This results in a change in temperature of the hot film probe and a change of resistance.