| 摘要 |
PURPOSE: A method for reducing return fuel in an LPI system is provided to improve fuel efficiency by reducing time for operating a fuel pump and to minimize the amount of the return fuel. CONSTITUTION: A method for reducing return fuel in an LPI system comprises following steps. A target pressure value of an engine injector is set(S101). A fuel pump is operated when a current pressure value(P) of the injector is lower than a target pressure value(S106). The fuel pump stops if the current pressure value is above the target pressure value multiplied by a predetermined value(S108). A duty ratio for operating the fuel pump is maintained if the current pressure value is same with the target pressure value after preparing the current pressure value to the target pressure value again(S110). The duty ratio for operating the fuel pump increases if the current pressure value is lower than the target pressure value after comparing the current pressure value to the target pressure value. [Reference numerals] (S101) Detecting an injector line pressure, P; (S105) Comparing P with a target pressure(P_target), P < P_target; (S107) Comparing P with the target pressure(P_target); (S109) Reducing a fuel pump PWM duty; (S110) Maintaining the fuel pump PWM duty; (S111) Increasing the fuel pump PWM duty |
