Inlet manifold

The system has main untreated air inlet (10), a moisture sensor (15), an evaluation unit (22), a main air inlet valve (16), an air filter (12) and an auxiliary untreated air inlet (11). The moisture sensor is arranged in the main inlet to detect moisture occurring there and the evaluation unit is connected to a further sensor outside the system for detecting other functions and forms logic for regulating the valve using the sensor signals. Independent claims are also included for the following: method of operating an induction system.