Fuel pressure control system

A fuel pressure control system configured to control a fuel pressure in a fuel supply system, the fuel supply system configured to supply fuel to an injector of an engine, the fuel pressure control system comprising:

• a booster pump configured to discharge fuel to a high-pressure system, which is a part of the fuel supply system, to increase a fuel pressure in the high-pressure system;
• a decompression mechanism configured to decompress the high-pressure system;
• and
• a control device configured to control the booster pump and the decompression mechanism, wherein
• the fuel pressure control system is configured to, when a discharge abnormality occurs as an abnormality in which a discharge flow amount of the booster pump becomes larger than a normal amount and the fuel pressure in the high-pressure system starts to rise, cause the decompression mechanism to perform a predetermined abnormality handling to stop the rise in the fuel pressure,
• the control device includes a state determiner configured to perform a state determination to determine whether a warning-required state arises to cause the fuel pressure in the high-pressure system possibly to exceed a predetermined threshold pressure, which is equal to or lower than a withstand pressure of the high-pressure system, if the discharge abnormality occurs before the abnormality handling stops the rise in the fuel pressure, and
• the control device is configured to start, on determination of the warning-required state, a warning control to cause a warning state in which the fuel pressure in the high-pressure system does not exceed the threshold pressure, even if the discharge abnormality occurs before the abnormality handling stops the rise in the fuel pressure.