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Air Flow Meter/Sensor: Description and Operation

Description
The Mass Air Flow Sensor installed between the air cleaner assembly and the throttle body (inserted the intake air hose). The type of mass air flow sensor is a hot wire and composed of a hybrid circuit, hot wire element (sensor ring) which made of a platinum wire, housing, protective grid, moulding ring. Mass air flow rate is measured by detection of heat transfer from a hot wire probe and the change of the mass air flow rate causes change in the amount of heat being transferred from the hot wire probe surface to the air flow. This results in the change of the temperature of the hot wire probe and in the change of "Resistance".