Patent attributes
Disclosed is a stuck-open failure detection system for a gas-fuel injection valve adapted to inject or supply gas fuel into/to a combustion chamber of an engine, which comprises: a shutoff value interposed in a fuel supply passage fluidically connected to the gas-fuel injection valve, at a position upstream of the gas-fuel injection valve, and adapted to supply gas fuel to the gas-fuel injection valve in its open state; an open/close controller for controllably opening and closing the shutoff value; a pressure detector for detecting a pressure in a region of the fuel supply passage between the gas-fuel injection valve and the shutoff value; and a stuck-open failure detector for detecting a stuck-open failure that the gas-fuel injection valve is stuck in the open state, based on a pressure change detected by the pressure detector. In this stuck-open failure detection system, the open/close controller is operable, in response to an operation for starting the engine, to open the shutoff valve and then close the shutoff valve after a lapse of a given time, and the stuck-open failure detector is operable to detect the stuck-open failure, based on a pressure change detected after the open/close controller closes the shutoff valve.