Abstract: The invention proposes a method for operating a metering system (32) with a plurality of metering valves (34, 35) for an SCR catalyst system, in which opening times for the injection of reducing agent are calculated for the metering valves (34, 35) based on a metering amount requirement. In the calculations of the opening times, a metering-valve-specific adaptation factor is used, w herein a deviation (?p) of a system pressure (pist) in the metering system (32) from a target pressure (psoll) and a weighting factor are used for calculation of the metering-valve-specific adaptation factor. The weighting factor depends on a proportion (r34, r35) of the required metering amount ((formula (I)), (formula (II)) of the respective metering valve (34,35) in relation to a total metering amount ((formula (I)), (formula (II)) of all metering valves (34, 35).

Abstract: The invention proposes a method for operating a metering system (32) with a plurality of metering valves (34, 35) for an SCR catalyst system, in which opening times for the injection of reducing agent are calculated for the metering valves (34, 35) based on a metering amount requirement. In the calculations of the opening times, a metering-valve-specific adaptation factor is used, w herein a deviation (?p) of a system pressure (pist) in the metering system (32) from a target pressure (psoll) and a weighting factor are used for calculation of the metering-valve-specific adaptation factor. The weighting factor depends on a proportion (r34, r35) of the required metering amount ((formula (I)), (formula (II)) of the respective metering valve (34,35) in relation to a total metering amount ((formula (I)), (formula (II)) of all metering valves (34, 35).

Abstract: A method for identifying deviations in quantity in the case of a fluidic metering system (100-165), in particular an internal combustion engine of a motor vehicle, in which at least one conveying pump (125) for conveying a fluid, and at least one pressure sensor (135) for determining a fluidic pressure in the metering system (100-165), are disposed, wherein it is provided in particular that a test admeasurement of fluid is carried out (205), that a temporal pressure drop in the metering system (100-165) is detected (210), that the detected temporal pressure drop is compared with a pressure drop (215) that is to be theoretically expected (220), and that a deviation in quantity of the metering system (100-165) is determined based on the result of the comparison (225).

Abstract: A method for identifying deviations in quantity in the case of a fluidic metering system (100-165), in particular an internal combustion engine of a motor vehicle, in which at least one conveying pump (125) for conveying a fluid, and at least one pressure sensor (135) for determining a fluidic pressure in the metering system (100-165), are disposed, wherein it is provided in particular that a test admeasurement of fluid is carried out (205), that a temporal pressure drop in the metering system (100-165) is detected (210), that the detected temporal pressure drop is compared with a pressure drop (215) that is to be theoretically expected (220), and that a deviation in quantity of the metering system (100-165) is determined by means of the result of the comparison (225).