What Are the Reasons for White Smoke from a Gasoline Engine?

[OOmar]

The reasons for white smoke from a gasoline engine are as follows: 1. High water content in the fuel. There are two main factors causing this situation: one is purchasing low-quality fuel with high water content; the other is a malfunctioning fuel-water separator, which fails to remove water from the fuel. In both cases, fuel containing water burns in the cylinder, producing large amounts of unburned hydrocarbons and water vapor, resulting in white exhaust gas that appears as white smoke. Solution: To address this issue, ensure the purchase of high-quality fuel and regularly inspect the fuel-water separator to ensure it is functioning properly, promptly removing any separated water. 2. Coolant entering the cylinder. Coolant may enter the cylinder due to damage to the cylinder liner or cylinder head gasket. When coolant enters the cylinder, it mixes with fuel under high temperature and pressure, producing large amounts of water vapor, which appears as white smoke when exhausted. Solution: Carefully inspect the cylinder liner and cylinder head gasket for cracks or damage. If damaged, replace them immediately. 3. Faulty fuel injector. In a normally operating engine, fuel in the cylinder is atomized for combustion. If a fuel injector in one cylinder malfunctions, the fuel it sprays forms droplets. When mixed with air and compressed, the temperature rises, causing the fuel to turn into vapor without combustion, resulting in white smoke. Solution: To resolve this issue, use a cylinder cut-off method to identify the faulty injector and replace it. 4. Insufficient fuel injection timing adjustment. In this case, the amount of fuel injected by the injector before combustion is small, reducing the pre-mixed gas volume. This not only slows the combustion speed but also extends the combustion end time, forming white mist. Additionally, delayed fuel injection in the next cycle causes unburned fuel to be exhausted, forming white fuel vapor, which appears as white smoke.