Method for operating a fuel injection system for supplying a combustion engine with fuel, and electronic control unit

The invention relates to a method for operating a fuel injection system (1) for supplying a combustion engine of a vehicle with fuel, in which method the fuel is conveyed at high pressure with the aid of a high-pressure pump (2), fed to a high-pressure accumulator (3), and injected into a cylinder of the combustion engine with the aid of at least one injector connected to the high-pressure accumulator (3). In order to detect any damage to the drive of the high-pressure pump (3), according to the inventiona) the pressure (P) in the high-pressure accumulator (3) is measured and, on the basis of the measured values, a pressure drop (ΔP) in the high-pressure accumulator (3) caused by an injection into a cylinder is determined,b) a maximum pressure gradient is determined during a pressure build-up phase following the injection,c) the determined pressure drop (ΔP) and the determined maximum pressure gradient are put into proportion.The invention further relates to an electronic control unit for carrying out the method.