What is the Optimal Amount of Fuel to Add to a Car?

[HarrisonFitz]

It is most appropriate to fill a car's fuel tank to two-thirds of its capacity. The hazards of overfilling the fuel tank are as follows: Risk of fire when exposed to open flames: When the fuel tank is overfilled, the expansion of gasoline volume can rupture the tank. Therefore, car designs include vent holes at the top. If the tank is overfilled, fuel may overflow through these vent holes. Moreover, gasoline is highly volatile, and if it comes into contact with an open flame, it can ignite instantly, causing irreparable damage. Blockage of vent holes: If the vent holes become blocked, negative pressure can develop inside the fuel tank, leading to poor fuel supply or even a complete failure to supply fuel. Symptoms such as the engine failing to start immediately after refueling or jerking movements during high-speed driving may be caused by an overfilled fuel tank.