Method and device for operating an internal combustion engine

Abstract

The invention relates to a method for operating an internal combustion engine (106) having at least two cylinders (102, 103, 104, 105) for a motor vehicle, comprising: determining a respective torqueoutput of the cylinders (102, 103, 104, 105), which occurs due to an injection of fuel into the respective cylinder (102, 103, 104, 105), determining a difference in the torque outputs, comparing thedifference in torque outputs to a specified threshold value for the torque output, determining a respective injection mass of the respective injection into the respective cylinder (102, 103, 104, 105), determining a difference in the injection masses, comparing the difference in the injection masses to a specified threshold value for the injection mass and, if the determined differences exceed therespective associated threshold, determining whether the respective torque outputs correspond with the associated injection mass and, if the respective torque outputs are outside of a specified tolerance range for a respective corresponding injection mass, modifying an injection time (T) in at least one of the cylinders (102, 103, 104, 105).

Description

technical field [0001] The invention relates to a method for operating an internal combustion engine. The invention also relates to a device for operating an internal combustion engine, which is designed to carry out the method. Background technique [0002] In motor vehicles with a so-called common rail injection system (also called accumulator injection system), several injectors, typically all injectors, are connected to a common fuel distributor (common rail) under high pressure coupled. The fuel injection quantities to be injected into the cylinders of the internal combustion engine in each case within a cylinder stroke (also referred to as a working stroke) are typically initially metered in such a way that with a selected shorter or longer actuation duration to drive the corresponding injectors to inject fuel into the corresponding cylinders. During the actuation duration, the injectors are respectively opened. [0003] Due to manufacturing tolerances and aging ph...

AI Technical Summary

Problems solved by technology

This can lead to torque differences between cylinders, which can adversely affect the smooth running or emissions performance of the internal combustion engine

Wear phenomena or deposits can therefore in particular lead to changes in the actual opening duration or actual opening degree of the injector for a given fuel pressure and actuation duration over the life of the injector

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