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.
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Hyundai Elantra AD (2016-2020) Owners Manual: Auto Defogging System (Only for Automatic Climate Control System)
Auto defogging reduces the possibility of fogging up the inside of the windshield
by automatically sensing the moisture of inside the windshield.
The auto defogging system operates when the heater or air conditioning is on.
Information
The auto defogging system may not operate normally, when ...