Intake manifold for internal combustion engine, positive crankcase ventilation system including same, and internal combustion engine

Abstract

The disclosed subject matter includes an intake manifold for an internal combustion engine that can have a labyrinth structure located therein configured to cause fluids, such as blow-by from engine exhaust, to move in a non-linear direction. The intake manifold can have a plenum including an inlet opening, a plurality of runners, each of the runners extending from the plenum and including a first end opened to the plenum and a second end configured to be connected to the internal combustion engine, and a ventilation chamber, the ventilation chamber extending along each of the runners. The ventilation chamber can include a plurality of ports spaced along the ventilation chamber, each port opens into a respective one of the runners, and a labyrinth inside the ventilation chamber and extending across the ventilation chamber.