WARNING
To reduce the risk of SERIOUS INJURY or DEATH:
Hyundai Elantra AD (2016-2020) Owners Manual: Sunvisor
To use a sunvisor, pull it downward. To use a sunvisor for a side window, pull
it downward, unsnap it from the bracket (1) and swing it to the side (2).
To use the vanity mirror, pull down the sunvisor and slide the mirror cover (3).
Adjust the sunvisor forward or backward (4) as needed. Use t ...
Hyundai Elantra AD (2016-2020) Service Manual: Repair procedures
Inspection
1.
After disconnecting the vapor hose from the PCV valve, remove the PCV valve.
2.
Reconnect the PCV valve to the vapor hose.
3.
Run the engine at idle, then put a finger over the open end
of the PCV valve and make sure that intake manifold vacuum can be felt.
  ...