Patent ID: 8374770
Filing Date: 2013-02-12
Classification: F02D

Abstract:
1. A method for adapting an injection characteristic curve of an internal combustion engine, with at least one cylinder, to age-related changes or production-related variations of an actual injection behavior, where at least one injector for injecting fuel is associated with each cylinder, the method comprising: a) when the internal combustion engine is in an operating mode that does not require an injection of fuel, opening a selected injector over a control period for injecting a minimum amount, wherein at least one working cycle with injector control follows or precedes at least one working cycle without injector control, b) determining a differential of two subsequent segment times of the internal combustion engine or another variable, which reproduces a temporal modification of a crankshaft angular velocity, as a measurement value for the working cycle with control and for the working cycle without control, respectively and c) forming a relation between the measurement values of the working cycles with and without control and using the relation to correct the injection characteristic curve, wherein the internal combustion engine operates with active ignition, the measurement value for the at least one working cycle with control being examined in order to take into account ignition faults and the aforementioned relation then only being used to correct the injection characteristic curve if the respective measurement value in the working cycle with injector control significantly deviates from the measurement value or the measurement values in the working cycle or in the working cycles without injector control.