METHOD AND SYSTEM FOR CONTROLLING LOW PRESSURE FUEL PUMP OF GASOLINE DIRECT INJECTION ENGINE

摘要

The present invention relates to a method and a system for controlling the low-pressure fuel pump of a gasoline direct injection (GDI) engine, wherein the method and system control the supply pressure of fuel in the GDI engine in which the fuel is directly injected into a combustion chamber. According to an embodiment of the present invention, the method for controlling the low-pressure fuel pump of the GDI engine in which the fuel primarily pressurized in a low-pressure system with the low-pressure fuel pump is directly injected into the combustion chamber through an injector after secondarily pressurized in a high-pressure system with a high-pressure fuel pump comprises: a step of receiving information about the malfunction of the high-pressure fuel pump; a step of raising fuel pressure in the low-pressure fuel pump to a set pressure (AP pressure) when the high-pressure fuel pump is judged to malfunction based on the information about the malfunction of the high-pressure fuel pump; and a step of controlling the fuel pressure in the low-pressure fuel pump based on measurement fuel pressure against target fuel pressure in the high-pressure fuel pump or the control value variation of the GDI engine when the high-pressure fuel pump does not malfunction.