Patent ID: 8583347

Claim:
A method for determining at least one rail pressure and closing current value pair for a pressure control valve of a common rail injection system of an internal combustion engine, comprising: operating the common rail injection system in a metering-unit control mode, during which a rail pressure is controlled using a metering-unit valve, the pressure control valve is closed, and the rail pressure is in a steady state; while in the metering-unit control mode, performing the following: reducing a control current for the pressure control valve; detecting a pressure curve over time in the common rail by monitoring the rail pressure; determining a rail pressure value as corresponding to a point on the detected pressure curve at which a drop in the rail pressure is detected, the drop caused by an opening of the pressure control valve in response to the reducing of the control current; and determining a closing current value corresponding to the rail pressure value; and associating the rail pressure value and the closing current value with the at least one rail pressure and closing current value pair.