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Air Flow Meter/Sensor: Description and Operation

Mass Air Flow (MAF) Sensor







The mass air flow (MAF) sensor is an air flow meter that measures the amount of air that enters the engine. It is fitted between the air cleaner and turbocharger. A small quantity of air that enters the engine indicates deceleration or idle. A large quantity of air that enters the engine indicates acceleration or a high load condition. The mass air flow (MAF) sensor assembly consists of a mass air flow (MAF) sensor element and an intake air temperature sensor that are both exposed to the air flow to be measured. The mass air flow (MAF) sensor element measures the partial air mass through a measurement duct on the sensor housing.