Abstract: The present invention relates to methods for charging at least one combustion chamber (12) of a spark-ignition combustion engine (10) with fuel and air. At least one combustion chamber charge is produced during a shutoff phase of the internal-combustion engine (10) and is ignited when the internal-combustion engine (10) is subsequently started. The methods are characterized in that, during the shutoff phase, at least one measure is taken to produce a high percentage of fuel vapor in the combustion chamber charge. The present invention also relates to a control unit for controlling the methods.

Abstract: A method for operating an internal combustion engine having at least one triggerable intake valve and at least one triggerable discharge valve, in which the internal combustion engine is directly started in a start-up operating mode and, following the start, is operated in at least one other operating mode. A starting discharge instant of a discharge valve of the internal combustion engine that is used during the start-up operating mode is retarded in time with respect to a standard discharge instant so as to improve the direct start-up characteristics of the internal combustion engine. In addition, to further improve the direct start-up characteristics, it is possible to retard a closing instant of an intake valve that is used during the start-up operating mode with respect to a standard closing instant.

Abstract: In a multi-cylinder combustion engine with a variable compression ratio a start of the combustion engine is performed with a compression ratio which is reduced relative to compression ratios in normal operation of the combustion engine.

Abstract: In a direct start of an internal combustion engine, sufficient energy may need to be released in a first combustion to set the internal combustion engine into motion, if possible without the assistance of an additional assembly, such as an electromotive starter. For this reason, the carburetion of an air-fuel mixture, made up of the air mass present in a combustion chamber and the fuel mass injected therein, is of great importance. In order to improve the mixture formation during a start, e.g., during a warm start of an internal combustion engine, the fuel mass required for a mixture formation is introduced into the combustion chamber, in full or in part, already prior to a start phase by at least one injection, and the mixture formation may be improved in this manner by vaporization of the introduced fuel mass.

Abstract: A method for starting an internal combustion engine, in particular of a motor vehicle, is described. The internal combustion engine has a plurality of cylinders and a starter motor. The internal combustion engine is set in motion by the starter motor, and fuel is injected directly into a combustion chamber of the internal combustion engine where it is combusted. Fuel, in the form of at least two partial injections, is injected into the particular cylinder that executes a first compression stroke after a starting onset, starting from which the internal combustion engine is set in motion, the injection taking place during the compression stroke into the combustion chamber.

Abstract: In a direct start of an internal combustion engine, sufficient energy may need to be released in a first combustion to set the internal combustion engine into motion, if possible without the assistance of an additional assembly, such as an electromotive starter. For this reason, the carburetion of an air-fuel mixture, made up of the air mass present in a combustion chamber and the fuel mass injected therein, is of great importance. In order to improve the mixture formation during a start, e.g., during a warm start of an internal combustion engine, the fuel mass required for a mixture formation is introduced into the combustion chamber, in full or in part, already prior to a start phase by at least one injection, and the mixture formation may be improved in this manner by vaporization of the introduced fuel mass.

Abstract: The method for direct start of an internal combustion engine with direct fuel injection into combustion chambers of the engine that are filled with air includes improving or increasing fuel vaporization in the combustion chambers when a start temperature (T) of the internal combustion engine is below a predetermined start temperature threshold (T_S). The apparatus for performing the method includes a control unit (20) for controlling direct start of the internal combustion engine.

Abstract: In a multi-cylinder combustion engine with a variable compression ratio a start of the combustion engine is performed with a compression ratio which is reduced relative to compression ratios in normal operation of the combustion engine.