What Causes the Suction Sound When Opening the Fuel Tank?

[EverlyRose]

Here are the specific reasons for the suction sound in the fuel tank: 1. Malfunction of the carbon canister or solenoid valve. The pressure inside the fuel tank is lower than the external pressure, which can cause the tank to deform. Severe deformation may prevent refueling. 2. When the pressure inside the fuel tank is lower than the external pressure and there is no ventilation with the outside, the fuel pump will draw outward. Over time, this may lead to damage to the fuel pump. 3. Continuous evaporation of fuel in the tank increases internal pressure. To mitigate the effects of vapor and prevent these fuel vapors from directly polluting the atmosphere, a pathway is designed between the car's fuel tank and the engine intake manifold.