Patent ID: 8800355

Claim:
A pressure accumulation fuel injection device having an injector that injects fuel into a cylinder of an internal combustion engine, a common rail that accumulates high-pressure fuel supplied from a high-pressure fuel supply pump and that supplies the fuel to the injector, and a fuel pressure sensing device that senses fuel pressure of the common rail, wherein the fuel injection device controls the fuel pressure of the common rail based on the fuel pressure sensed with the fuel pressure sensing device, the fuel injection device comprising: a pressure reducing valve that reduces the fuel pressure of the common rail; a temporary abnormality determining means for temporarily determining that the fuel pressure sensing device is abnormal when change of the fuel pressure sensed with the fuel pressure sensing device is smaller than a preset temporary abnormality determination value; and a formal abnormality determining means for formally determining that the fuel pressure sensing device is abnormal when both a first change of the fuel pressure and a second change of the fuel pressure are smaller than a preset formal abnormality determination value, wherein after the temporary abnormality determining means temporarily determines that the fuel pressure sensing device is abnormal, the formal abnormality determining means detects the first change in the fuel pressure with the fuel pressure sensing device by reducing the fuel pressure with the pressure reducing valve after fuel injection from the fuel injector, the formal abnormality determining means detecting the second change in the fuel pressure with the fuel pressure sensing device by increasing fuel transfer quantity from the high-pressure fuel supply pump after reducing the fuel pressure with the pressure reducing valve.