Process for determining a fuel pressure and/or a quantity of injected fuel comprises dosing fuel from a fuel injection unit (100) of an internal combustion engine as a function of a first and a second control signal (A1, A2). The first control signal controls the start and end of the fuel dosing and the second control signal controls the pressure build-up. The course of the pressure is determined using at least the first control signal and the second control signal. Independent claims are also included for the following: (1) Device for carrying out the above process; (2) Computer program; (3) Computer program product; and (4) Digital storage medium, especially a diskette. Preferred Features: Variables are specified which characterize the start of the pressure build up, the start of fuel dosing, and/or the end of fuel dosing.
