Abstract: The invention relates to two methods for controlling a fuel metering of a direct-injection internal combustion engine (10) in a multiple injection operating mode according to which at least two fuel injections into a cylinder (12) are carried out during a compression cycle of the cylinder (12) of the internal combustion engine (10) by means of at least one injection valve (22). The invention provides that a pressure (rail pressure, PR), under which the fuel is stored in front of the injection valve (22), is present in such a manner and/or injected fuel portions of the individual injections of a combustion cycle and/or a total fuel quantity, which is injected during a multiple injection, are varied in such a manner as to prevent a forthcoming valve opening time (?t) of the injection valve (22) from falling below a preset valve opening time (?tK) during at least one injection of a combustion cycle.

Abstract: An exhaust gas system of an internal combustion engine, including a catalyst, and a cooling section provided upstream of the catalyst. The cooling section includes an additional cooling arrangement provided so that in all operating phases of the internal combustion engine with their different exhaust gas mass flow rates, the amount of thermal energy dissipated from the exhaust gas relative to a total amount of thermal energy present in the exhaust gas (relative heat dissipation) is increased in such a way that a maximum temperature reduction is obtained at intermediate values of the exhaust gas mass flow rate.

Abstract: The invention relates to a method for warming up at least one catalytic converter that is arranged downstream from a spark-ignition, direct injection internal combustion engine. To this end, an exhaust gas temperature is at least temporarily increased by at least one measure, which is executed by the engine, after the conclusion (t1) of the engine start of the internal combustion engine. The measures, which are executed by the engine, consist of a multiple injection during which at least two fuel injections into the cylinder are carried out within an induction cycle and compression cycle of a cylinder of the internal combustion engine, and/or said measures consist of a spark retarding. The invention provides that the measure executed by the engine or a combination of measures having the strongest heating action is available, at the earliest, after a retardation of at least two working cycles of the internal combustion engine after the conclusion (t1) of the engine start.

Abstract: The invention relates to a method for at least temporarily increasing an exhaust gas temperature of a spark-ignition, direction injection internal combustion engine (10) involving at least one measure, which is executed by the engine, whereby this at least one measure consists of a spark retarding and of a multiple injection (ME). During the multiple injection (ME), at least two fuel injections into the cylinder (12) are carried out within an induction cycle and compression cycle of a cylinder (12) of the internal combustion engine (10), and the latest of these injections ensues during a compression cycle of the cylinder (12). The invention also relates to the utilization of the method.

Abstract: The invention relates to two methods for controlling a fuel metering of a direct-injection internal combustion engine (10) in a multiple injection operating mode according to which at least two fuel injections into a cylinder (12) are carried out during a compression cycle of the cylinder (12) of the internal combustion engine (10) by means of at least one injection valve (22). The invention provides that a pressure (rail pressure, pR), under which the fuel is stored in front of the injection valve (22), is preset in such a manner and/or injected fuel portions of the individual injections of a combustion cycle and/or a total fuel quantity, which is injected during a multiple injection, are varied in such a manner as to prevent a forthcoming valve opening time (&Dgr;t) of the injection valve (22) from falling below a preset valve opening time (&Dgr;tK) during at least one injection of a combustion cycle.

Abstract: An exhaust gas system of an internal combustion engine, including a catalyst, and a cooling section provided upstream of the catalyst. The cooling section includes an additional cooling arrangement provided so that in all operating phases of the internal combustion engine with their different exhaust gas mass flow rates, the amount of thermal energy dissipated from the exhaust gas relative to a total amount of thermal energy present in the exhaust gas (relative heat dissipation) is increased in such a way that a maximum temperature reduction is obtained at intermediate values of the exhaust gas mass flow rate.

Abstract: A device for supplying exhaust gases from an internal combustion engine to a catalytic converter, having multiple exhaust gas supply lines including at least one exhaust gas supply line that serves as a heat-conveying line to promote a transfer of exhaust gas heat to the catalytic converter and at least one other exhaust gas supply line that serve as a heat exchanger to promote an extraction of heat from the exhaust gas upstream of the catalytic converter. A switchable control mechanism controls a flow cross-section of at least one of the exhaust gas supply lines.

Abstract: A method for operating an internal combustion engine of a motor vehicle with a butterfly valve, where the butterfly valve is opened and a fuel supply is cut off when the vehicle is in an overrun phase, the method including the steps of determining a first value of a position of the butterfly valve during the overrun phase as a function of a vehicle speed and an engine rpm value at a beginning of the overrun phase, adjusting the butterfly valve to the first value during the overrun phase; and adjusting the butterfly valve to a second value, which is calculated as a function of the vehicle speed and the engine rpm's, instead of to a value based on a gas pedal position for a certain predetermined time after an end of the overrun phase.