Crankcase Ventilation Systems: Operation: 18i

Oil fumes from the crankcase are routed to an oil separator, then drawn through one of 2 circuits into the engine. The upper circuit leads to a throttle body port just downstream from the airflow sensor, and the hose contains a 0.197" (5 mm) orifice. The lower circuit leads to the intake manifold and is connected to the fuel evaporation system. A 0.067" (1.7 mm) orifice is used near the oil separator, and a 0.079" (2 mm) orifice is provided in the hose to the carbon canister.