PCV Valve Ventilation Hose

WARNING: This page is about a different car, the 2005 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.

Check hoses and hose connections for leaks.
Disconnect all hoses and clean with compressed air. If any hose cannot be freed of obstructions, replace.

Fig 1: Checking Positive Crankcase Ventilation Valve Hose
Courtesy of NISSAN MOTOR CO., U.S.A.