| 摘要 |
PROBLEM TO BE SOLVED: To provide an abnormality determination device capable of determining abnormality of a pressure reduction valve disposed in a fuel system.SOLUTION: An abnormality determination device is applied to a fuel system having a port injection valve and a cylinder injection valve, a low-pressure pump, a high-pressure pump, and a pressure reduction valve on a fuel supply passage. A control portion disposed in the device instructs a discharge amount to the low-pressure pump to discharge the total of a fuel request amount, a feedback amount of a port injection fuel pressure, and a correction amount set to a discharge amount by the pressure reduction valve when valve-opening is instructed to the pressure reduction valve, and set to zero when valve-closing is instructed. Further it instructs a discharge amount to control a cylinder injection fuel pressure to the high-pressure pump. The control portion determines abnormality on the basis of transition of the fuel pressure in changing the instruction to the pressure reduction valve without changing the correction amount while inhibiting port injection and lowering a response speed in feedback control.SELECTED DRAWING: Figure 7 |
