1.9.2 Diagnosis of a leakage in the PCV-System

A disconnection or leakage in the PCV-System is indicated by a rough or stalling engine and results in a reaction within the fuel system (fuel trim deviation).

In this case a fault code will be stored by the fuel system monitoring.

Fig 1: Positive Crankcase Ventilation System Diagram

Courtesy of BMW OF NORTH AMERICA, INC.

Fig 2: Identifying Intake Air System, Blowby Tube And Integrated Oil Separator

Courtesy of BMW OF NORTH AMERICA, INC.