A method is disclosed of controlling operation of a fuel injector in response to measuring a quantity of fuel injected by the fuel injector from a fuel accumulator to an engine cylinder during operation of a fuel pump that delivers fuel to the accumulator, comprising: determining an average pressure of the fuel accumulator during a first time period before a fuel injection event; predicting a mass of fuel delivered to the fuel accumulator during a pumping event (Q.sub.pump); determining an average pressure of the fuel accumulator during a second time period after the fuel injection event; estimating a leakage of fuel; computing the injected fuel quantity by adding the average pressure during the first time period to Q.sub.pump, and subtracting the average pressure during the second time period and the leakage; and using the computed injected, fuel quantity to control operation of the fuel injector.

A vehicle, a vehicle fuel reactant leak detection system, a computer program product, and a computer implemented method of detecting leakage of a fuel reactant from a vehicle. The vehicle includes one or more fuel cell modules, a fuel supply source to supply a fuel reactant to the one or more fuel cell modules via a high-pressure fuel supply line, a fuel supply valve configured to open and close fuel reactant flow through the high-pressure fuel supply line, and a computing device, operatively connected to the fuel supply source. The computing device includes one or more processors caused to conduct, in response to a detection as sensor data of pressure in the high-pressure fuel supply line when the vehicle engine is in a non-operating state, fuel pressure analysis of the sensor data, and detect, based on the fuel pressure analysis, leakage of the fuel reactant at the fuel supply valve.

A leak detection system is provided with a first window configured to mount at a first opening in a first wall portion in an enclosure (e.g., for a gas turbine engine or other equipment in a power plant). The leak detection system includes a leak sensor configured to transmit a beam through the first window and an interior of the enclosure to obtain sensor feedback. The leak detection system includes a controller configured to evaluate the sensor feedback to monitor for a leak of a hazardous fluid in the enclosure.

Methods and systems are presented for diagnosing a breach of an evaporative emissions system. The methods and systems include repurposing a resonator as a vacuum reservoir to reduce a pressure of an evaporative emissions system so that it may be determined if there is or is not a breach of the evaporative emissions system.

A method for detecting valve leakage of a least one valve at a cylinder intake manifold or exhaust manifold of a vehicle engine, the method comprising: acquiring a set of pressure data points indicative of the pressure in the cylinder intake manifold or exhaust manifold for crankshaft angular positions covering crankshaft angular rotation degrees such that each of the at least one valve has opened at least one time; and determining at least one test value based on the set of pressure data points, wherein a valve leakage is detected based on a comparison of the at least one test value to a threshold value.

A method for operating an injection system of an internal combustion engine, including: providing the injection system includes a high pressure accumulator; regulating a high pressure in the high pressure accumulator in a normal operation by way actuating a low pressure-side suction throttle; regulating the high pressure in a first operating mode of safety operation by way of actuating at least one high pressure-side pressure control valve; carrying out a switchover from the normal operation into the first operating mode of safety operation if the high pressure reaches or exceeds a first limit pressure value; and carrying out a switchover from the first operating mode of safety operation into the normal operation if, starting from above a setpoint pressure value, the high pressure reaches or undershoots the setpoint pressure value, which is lower than the first limit pressure value.

The present disclosure relates to a method for controlling pressure of an engine, including a controller structured to implement the method and an engine system including the controller. More specifically, the present disclosure relates to a method based on a mass balance analysis of a fuel system to determine how much mass needs to be pumped to maintain or achieve a certain pressure for the engine. In some embodiments, the method analyzes how much mass can be pumped by each pumping event based on current engine conditions. The analysis is performed over the smallest repeatable pump events and cylinder events cycle, or “subcycle,” based on the number of pump events and cylinder events for a given engine configuration.

Methods and systems are provided for diagnostics of a fuel system configured with a three-way isolation valve and a four port canister. An example method includes, during a refueling event, indicating degradation of the three-way isolation valve based on pressure in the fuel tank during depressurization followed by refueling.

A method that includes coupling an external, removable fuel pressurization system to a fuel system of a vehicle. The fuel system of the vehicle is pressurized with the fuel pressurization system while the vehicle is parked and without activating a fuel consumer (e.g., an engine) of the vehicle. Decay of pressure of the fuel system is monitored following pressurization of the fuel system, and one or more of a leak, or a replaceable component, of the fuel system of the vehicle is detected based on at least in part on the decay of pressure that are monitored.

A method for detecting leakage of a high pressure fuel pump of a vehicle includes: turning off starting of an engine; after the starting of the engine is turned off, determining whether restarting of the engine occurs by a fuel rail pressure condition in which internal fuel pressure of a fuel rail connected between the high pressure fuel pump and an injector of the engine is less than or equal to a reference pressure; when the restarting of the engine occurs by the fuel rail pressure condition, determining whether a reference pressure reach time of the internal fuel pressure of the fuel rail is less than or equal to a reference time; and when the reference pressure reach time of the internal fuel pressure of the fuel rail is less than or equal to the reference time, storing a number of times of restarting of the engine.