Why is there a strong gasoline smell after starting the car?

[SanStephen]

A strong gasoline smell after starting the car is caused by incomplete combustion of fuel. When the car starts in a cold state, the engine control unit (ECU) increases the fuel injection volume based on intake air temperature and coolant temperature signals. At this time, the engine has not yet reached normal operating temperature, resulting in poor combustion efficiency. This causes some fuel to be expelled without complete combustion, hence the strong gasoline smell during cold starts. If the heavy gasoline smell persists after the car has been running for a while, it likely indicates a malfunction. Common faults include: 1. Insufficient air intake through the throttle body, causing incorrect air flow data that affects fuel injection quantity and increases fuel consumption, leading to stronger gasoline odor; 2. Excessive carbon buildup in combustion chambers or on pistons, resulting in insufficient cylinder pressure and over-rich air-fuel mixture that increases fuel consumption; 3. Severe carbon deposits inside the engine affecting proper air-fuel mixture atomization; 4. Gasoline pipe leakage forming sludge at connection points, with odors entering the cabin through the air conditioning system.