Why can't the fuel tank cap of Volkswagen Tiguan be opened?

[LeonardoLynn]

It is highly possible that the fuel tank cap of Volkswagen Tiguan cannot be opened due to a damaged motor. Here is a detailed introduction about it: 1. When the pressure inside the fuel tank is lower than the external pressure: It may cause deformation of the fuel tank. If the deformation is severe, it might even prevent refueling. 2. When the pressure inside the fuel tank is lower than the external pressure: If the tank is not vented, the fuel pump will continuously draw fuel out, which over time may lead to damage of the fuel pump. 3. Tire pressure monitoring: Most vehicle fuel tank caps also indicate the recommended tire pressure values under different load conditions.