FUNCTIONAL CHECKS

1. After disconnecting the ventilation hose from the PCV valve, remove the PCV valve from the cover and reconnect the PCV valve to the ventilation hose.
2. Run the engine at idle, then place your thumb over the end of the valve to check for vacuum.
3. If no vacuum exists, check for plugged hoses, manifold port vacuum at the throttle body or a defective PCV valve.

   Fig. 1: Check for vacuum at the PCV valve by placing your thumb over the end of the valve while the engine is idling

4. Inspect the valve as follows:
   1. Insert a thin stick into the positive ventilation valve from the threaded side to check that the plunger moves. If the plunger does not move, the PCV valve is clogged.

      Fig. 2: Inspecting the PCV valve for plunger movement