| 摘要 |
The present invention addresses the problem that in a fuel injection control system for an internal combustion engine provided with a low pressure fuel pump and a high pressure fuel pump, delivery pressure of the low pressure fuel pump can be decreased as much as possible, while avoiding the generation of vapor of fuel. In order to solve this problem, the invention resides in a fuel injection control system for an internal combustion engine in which a driving signal for a high pressure fuel pump is calculated by using proportional plus integral control based on a difference between a delivery pressure of the high pressure fuel pump and a target pressure thereof, and a delivery pressure of a low pressure fuel pump is caused to decrease when an amount of change per unit time of an integral term shows a decreasing tendency or zero, whereas the delivery pressure of the low pressure fuel pump is caused to increase when the amount of change per unit time of the integral term shows an increasing tendency, wherein in cases where an increase in the integral term resulting from a change in the target delivery pressure of the high pressure fuel pump has occurred, the increase in the delivery pressure of the low pressure fuel pump is prohibited. |
