Fresh air system for an internal combustion engine

The invention relates to a fresh air system for supplying combustion chambers of an internal combustion engine with fresh air, - with a housing (2) through which at least one fresh air path extends, - with a valve mechanism (3) which comprises at least one flap (5) adjustably mounted on the housing (2), which between a closed position in which it closes the fresh air path in a fluid-tight manner and an open position in which it releases the fresh air path for fresh air to flow through, is rotationally adjustable, - wherein the valve mechanism (3) comprises a spring-elastic biasing element (6) which is supported on the housing (2) and biases the flap (5) either towards the open or the closed position.