Air charging

Why an engine needs crankcase ventilation, how coarse labyrinth and fine cyclone oil separators remove oil from the crankcase gases, where the oil drains and how the pressure control valve protects the seals — with examples from different engines.

1.8 TFSI engine crankcase gas path: coarse and fine oil separators, pressure control valve, intake and turbocharger check valves, fresh air supply via PCV valve.

Why the intake ports have flaps, how they make the air swirl in petrol and diesel engines, how tilted flaps differ from swirl flaps, how the actuator and sensor work and how a two-stage variable-length manifold operates — with examples from different engines.

How an electronic throttle works: the pedal with two sensors, the throttle valve module with its electric motor, the stops and limp-home position, monitoring by two processors, the EPC lamp and what happens when the sensors fail — with examples from different engines.

Polyamide intake manifold module with trough-shaped flaps on a plastic shaft, fuel vapor recovery with a double check valve, and a mechanical vacuum pump with a swinging vane.