Abstract: In a method and a device for identifying the fuel quality in a fuel tank of an internal combustion engine, a reference volume with fuel is provided, which does not intermix with the fuel in the fuel tank when the fuel tank is refilled. After startup of the internal combustion engine, fuel from the fuel tank and from the reference volume is sequentially sucked into the internal combustion engine and parameters which depend from the fuel quality of the sucked-in fuel are measured and evaluated for both the fuel tank and the reference volume. If the parameter differ from one another, it can be concluded that the fuel quality of the fuel in the fuel tank before startup of the internal combustion engine has changed. A quantity (fuel factor) can then be taken into consideration in the mixture pre-control.

Abstract: In a method and a device for identifying the fuel quality in a fuel tank of an internal combustion engine, a reference volume with fuel is provided, which does not intermix with the fuel in the fuel tank when the fuel tank is refilled. After startup of the internal combustion engine, fuel from the fuel tank and from the reference volume is sequentially sucked into the internal combustion engine and parameters which depend from the fuel quality of the sucked-in fuel are measured and evaluated for both the fuel tank and the reference volume. If the parameter differ from one another, it can be concluded that the fuel quality of the fuel in the fuel tank before startup of the internal combustion engine has changed. A quantity (fuel factor) can then be taken into consideration in the mixture pre-control.

Abstract: A method for controlling boost pressure in an internal combustion engine is provided. The method includes a boost pressure control device, which is used to control the boost pressure in an internal combustion engine. The boost pressure control device includes a bypass unit, preferably in the exhaust gas flow of the internal combustion engine. The bypass unit includes an actuating device which enables the bypass unit when a predetermined actuating device setpoint value is reached. An adapted value is established as the correction value (pwgad) as a function of preset and/or detected internal combustion engine parameters (rlsol, nmot). The adapted value is used to adapt the setpoint value for the actuating device, which is specified as a function of the operating point, for a predetermined control deviation between a boost pressure actual value and a boost pressure setpoint value.

Abstract: The invention relates to a method for controlling boost pressure in an internal combustion engine, comprising a boost pressure control device by means of which the boost pressure in an internal combustion engine is controlled, the boost pressure control device having a bypass unit, preferably in the exhaust gas flow of the internal combustion engine, and the bypass unit having an actuating device which enables the bypass unit when a predetermined actuating device setpoint value is reached. According to the invention, an adapted value is established as the correction value (pwgad) as a function of preset and/or detected internal combustion engine parameters (rlsol, nmot), by means of which the setpoint value for the actuating device, which is specified as a function of the operating point, for a predetermined control deviation is adapted between a boost pressure actual value and a boost pressure setpoint value.

Abstract: A reciprocating internal-combustion engine having at least two gas intake ports (3) with gas intake valves (6), at least one gas exhaust port (4) with a gas exhaust valve (7) and at least one ignition device (14) per cylinder (1) is provided. The engine can also include a combustion chamber (1.1) formed by a cylinder cover (2.1) and a crown (11.1) of a piston (11). A trough-shaped recess (12) can be provided in the piston crown (11.1) and is bounded by a trough base (12.1) and side walls (16). The recess (12) can intersect a roof ridge (11.2) on the piston crown (11.1) and the trough base (12.1) slopes towards a fuel injection nozzle (8) and ends in a wall zone (12.2) extending steeply upwards on its side facing the fuel injection nozzle (8).

Abstract: A reciprocating internal-combustion engine having at least two gas intake ports (3) with gas intake valves (6), at least one gas exhaust port (4) with a gas exhaust valve (7) and at least one ignition device (14) per cylinder (1), and having a combustion chamber (1.1) formed by the cylinder cover (2.1) and the crown (11.1) of the piston (11), which is guided in the cylinder (1) in a reciprocating manner, into which combustion chamber the gas intake ports open at a flat angle of less than 45 degrees, measured in relation to the cylinder-head plane (2.1), wherein the piston crown (11.1) on the one hand and the cylinder cover (2.1) on the other hand are substantially roof-shaped in vertical section, wherein in each case one of the roof surfaces is associated with the gas intake valves (6) and the other roof surface is associated with the gas exhaust valve (7), and the orientation of the roof surfaces of the cylinder cover (2.1) corresponds to the orientation of the roof surfaces of the piston crown (11.