What are the reasons for difficulty in starting a car after filling up with fuel?

[SanKing]

There are several reasons why a car may be difficult to start after filling up with fuel: 1. Vapor lock: Gasoline evaporates very quickly at high temperatures. If the car is frequently driven with a low fuel level in high-temperature environments, vapor lock can form in the fuel lines. 2. Damaged charcoal canister: The charcoal canister is designed to absorb gasoline vapors generated in the fuel tank, thereby reducing the emission of gasoline vapors. If the fuel tank is overfilled, gasoline may splash into the charcoal canister, saturating the activated charcoal with fuel and rendering the canister ineffective. 3. Insufficient fuel supply: Gasoline tends to expand in hot weather. Overfilling the fuel tank can create negative pressure inside the tank, leading to insufficient fuel supply and subsequently affecting the car's ignition.