Repair Procedures: Inspection

WARNING: This page is about a different car, the 2021 Kia Seltos. However, it is still accessible from the selected car via links, so may be relevant.

After disconnecting the vapor hose from the PCV valve, remove the PCV valve.
Reconnect the PCV valve to the vapor hose.
Inspect the PCV valve for proper operation.
1. Run the engine at idle.
2. Put a finger on the open end of the PCV valve.
3. Make sure that intake manifold vacuum can be felt.
NOTE: The plunger inside the PCV valve will move back and forth with vacuum.

Courtesy of KIA MOTORS AMERICA, INC.
If the vacuum is not felt, clean or replace the vapor hose.