Where is the sensor for the left middle air vent of the Audi A6 located?

[LeTravis]

Audi A6's left middle air vent sensor is located under the hood. Definition of the sensor: It detects engine speed, hence also known as the speed sensor; it detects the top dead center position of the piston, thus also referred to as the top dead center sensor, including detecting the top dead center signals for each cylinder used for ignition control and the first cylinder top dead center signal for sequential fuel injection control. Working principle of the sensor: The function of the crankshaft position sensor is to determine the position of the crankshaft, i.e., the angle of the crankshaft and the engine speed. It usually works in conjunction with the camshaft position sensor to determine the basic ignition timing.