PCV Valve
REMOVAL
1. Disconnect the ventilation hose from the PCV valve. Remove the valve from the cylinder head cover and connect it to the ventilation hose.

2. Start the engine and let it idle. Cover the valve opening with your finger and check that vacuum is felt from the intake manifold.
At this time, the PCV valve plunger will move back and forth.
3. If no vacuum is felt, clean the PCV valve and ventilation hose in a cleaning solution (solvent) or replace them as necessary.
INSPECTION
1. Remove the PCV valve.
2. Insert a thin rod into the PCV valve from the threaded side and, moving the rod back and forth, check that the plunger moves.

3. If the plunger does not move, there are deposits in the PCV valve. In this case, clean or replace the valve.
INSTALLATION
Install the PCV valve and tighten it to the specified torque.
Tightening Torque:
PCV Valve: 8 - 12 N·m

POSITIVE CRANKCASE VENTILATION (PCV) VALVE OPERATION
Test yourself
A quick Hyundai Elantra CN7 quiz: every answer comes with an explanation and a link to the manual page.