PCV Valve: Inspection

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT PCV VALVE
1. Install a clean hose to the case side of the PCV valve
2. Blow air into the case side, and check that air passes through easily.
  CAUTION: Do not suck air through the valve. Petroleum substances inside the valve are hazardous to your health.
  
  If the results are not as specified, replace the PCV valve
  
  Fig 1: Blowing Air Into Case Side
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Remove the hose from the PCV valve.
4. Install a clean hose to the intake manifold side of the PCV valve.
5. Blow air into the intake manifold side, and check that air passes through with difficulty.
  If the results are not as specified, replace the PCV valve.
6. Remove the hose from the PCV valve.
  
  Fig 2: Blowing Air Into Intake Manifold Side
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002