Crankcase Ventilation (CV) System Inspection

Test for vacuum at the vacuum hose where it connects to the Crankcase Ventilation (CV) housing. There should be manifold vacuum present at the hose. If there is no vacuum, inspect for a plugged hose, leaking hose or a plugged vent adapter.
Plug the end of the vacuum hose while the engine is running. Inspect the hose for any areas that collapse when the end of the hose is blocked. Replace the hose if it collapses when blocked.
If oil has accumulated in the intake air duct, inspect for plugged vacuum orifice in crankcase ventilation housing, plugged or restricted crankcase ventilation housing, and excessive crankcase pressure or blow-by. See ENGINE COMPRESSION TEST under MECHANICAL INSPECTION under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES - 3.2L CTS article.
Inspect for a plugged or leaking fresh air vent hose assembly or vent adapter, plugged or restricted passages in the throttle body, missing or damaged "O" ring seals on the vent adapter and inspect the cam covers, the oil pan gasket, and other sealing areas for leaks.