What is a Mass Air Flow Sensor?
The Mass Air Flow Sensor (MAFS) is a sensor that is placed into the "Air Intake" system of an electronic control system and measures air flow (inhaled into the engine) that passed through the air intake. There arevarious types of MAFS, such as Karman Vortex Type and Mobile Flap Type. The wire is (placed) in the air passage way and heated by electric current. When air flows passed the wire, the wire cools and the temperature changes. These changes are converted into electrical signals and the amount of air flow is then measured. Because the air inhalation resistance is less than "Mobile Flap Type" and the measurement scope is wider, it is widely accepted by the car manufacturer.
Air Intake System
Air inhaled into the engine goes into the MAFS through an Air Cleaner and the Air Flow Rate and temperature are measured. This information is then sent to the ECU. The air from the MAFS goes into the combustion chamber through the throttle chamber.