Common faults of fuel water separator 

1. Unstable acceleration of the engine or failure of acceleration and emission of black smoke
The high-pressure fuel injector in the high-pressure common rail system requires precise control of fuel injection pressure, fuel injection time, and fuel injection volume, and the workmanship of the fuel injector is relatively fine. If there is a problem with the oil-water separator, the water and impurities in the diesel fuel will wear and tear the plunger and even parts in the fuel injection nozzle until the fuel injector is stuck. At the same time, explosive damage will occur to the spherical surface of the valve assembly. This results in an increase in the amount of fuel in the injector. It will cause unstable or weak acceleration of the engine, or emit black smoke and other malfunctions. In severe cases, it will directly damage the engine. Due to the fine workmanship of the fuel injector, its price is relatively high. For the above reasons, when there is a problem with the fuel-water separator, it must be replaced in time.

2. Prone to carbon deposits
If the fuel water separator is damaged, the water and impurities in the diesel will pass through the filter device, and then accumulate in the intake valve, intake duct, and cylinder, forming hard carbon deposits over time, which will affect the operation of the engine, and in severe cases, it will cause the engine to be destroyed.
Damage to the oil-water separator will cause valve carbon deposits, and valve carbon deposits will cause abnormalities such as engine starting difficulties, unstable idle speed, poor acceleration, rapid refueling and tempering, excessive exhaust gas, and increased fuel consumption. In severe cases, it will cause engine damage.

3. Engine emits white smoke
The damage of the fuel water separator will cause the engine to emit white smoke, because the water in the fuel will turn into water vapor when it is burned, so white smoke will appear. The water vapor in the white smoke will damage the high-pressure fuel injectors, resulting in insufficient engine power, and sudden shutdowns. In severe cases, the engine will be directly damaged.