Why is the valve cover gasket of the Passat leaking oil?

[MilaFitz]

If the engine valve cover gasket leaks oil for too long, it can cause the sealing components to shrink, harden, and lose elasticity, and in severe cases, even break. Reasons for valve cover gasket oil leakage: aging of the valve cover gasket, leading to poor sealing and oil leakage; clogging of the crankcase forced ventilation valve, causing increased crankcase pressure, which releases pressure from the valve cover gasket or other weak points, resulting in oil leakage. Engine oil leakage: Engine oil leakage poses significant safety hazards, as oil adhering to high-temperature components like the exhaust pipe or catalytic converter can easily cause vehicle fires. Especially during hot summer days when the engine and surrounding temperatures are high, special caution is needed to prevent vehicle fire accidents.