HIGH PRESSURE FUEL SYSTEM CONTROLS, DIAGNOSTICS, AND PROGNOSTICS USING FUEL MASS CHANGE ESTIMATES

A method includes operating a pump to pump fuel to a rail and concurrently operating one or more injectors to inject fuel from the rail into one or more cylinders of an engine. The method further includes filtering measurements of fuel pressure of the rail to determine filtered pressures for at least a first pressure measurement zone preceding a target event and a second pressure measurement zone succeeding a target fuel mass change event, determining a pressure change in response to the filtered pressures, and determining a fuel mass change of the target event in response to the pressure change.