Robert Boschgmbh

Wolfgang Tiebel

Holger Jessen

Michael Kessler

Jens Damitz

Christian Brinkmann

Thomas Federlein

Roman Meyer

In a method for cylinder equalization of a lambda-controlled internal combustion engine of a motor vehicle, cylinders to be tested are trimmed with respect to the mixture composition of metered fuel, and the cylinder equalization is carried out on the basis of an uneven running or uneven running change of the internal combustion engine caused by the trimming. In addition, the uneven running or uneven running change is detected in a reference state of the internal combustion engine. The uneven runnings or uneven running changes detected during successive trimmings of the cylinders to be tested are and compared to the uneven running values detected in the reference state.

Method for cylinder equalization of a lambda-controlled internal combustion engine, in particular of a motor vehicle

A method is described for operating an internal combustion engine, having a plurality of cylinders in an homogeneous operation, in which an exhaust gas lambda value and an unsteady running of the internal combustion engine are recorded, a mixture composition being cyclically varied, at least intermittently. In a test operation, the mixture composition is cyclically varied, in a selected cylinder, about a determined lambda value, whereas meanwhile the mixture composition is held constant in the remaining cylinders. From the magnitude of a cyclical fluctuation of the unsteady running or of a variable characterizing this, one may conclude upon a trimming of the mixture composition in the selected cylinder.

Method for operating an internal combustion engine having a plurality of cylinders in homogeneous operation

In a method for operating an internal combustion engine having multiple cylinders, a cylinder to be checked is diagnosed for an injection quantity error. During a normal operation, a first air/fuel ratio is predefined for the multiple cylinders, and a first uneven running is ascertained. During an adjustment operation, a second air/fuel ratio for the cylinder to be checked is predefined during a number of working cycles. During the adjustment operation, a second uneven running is ascertained. The injection quantity error is ascertained for the cylinder to be checked as a function of the first uneven running and the second uneven running.

Method for operating an internal combustion engine

A method for operating an internal combustion engine, particularly of a motor vehicle. The internal combustion engine has a combustion chamber and an injection valve by which fuel is able to be supplied to the combustion chamber, directly or via an intake manifold. In the method, a maximum combustion chamber pressure and a signal for a start of the injection of fuel is determined, and the signal for the start of injection is influenced as a function of the maximum combustion chamber pressure. A signal for an injection duration of fuel is determined and influenced as a function of the maximum combustion chamber pressure.

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Stuttgart, Germany

Wolfgang Tiebel