Patent ID: 8479509

Claim:
A method for operating an internal combustion engine with a plurality of cylinders, which are each assigned an inlet valve, an outlet valve and a combustion space, with an inlet camshaft connected to a camshaft adjuster, with an outlet camshaft connected to a camshaft adjuster, with a switchable inlet-valve drive which has a plurality of inlet cams for actuating a respective inlet valve, with a switchable outlet-valve drive which has a plurality of outlet cams for actuating a respective outlet valve, and with an exhaust-gas system, the method comprising: operating the internal combustion engine with compression ignition or with spark ignition as a function of an operating point, setting a specific residual exhaust-gas quantity in the combustion space for compression ignition, operating the internal combustion engine as a function of the operating point by an outlet cam, by which a first outlet opening phase and a second outlet opening phase take place, the second outlet opening phase commencing during an inlet opening phase, setting the residual exhaust-gas quantity in the combustion space at a first operating point in a compression-ignition mode as a function of a valve interference set between the inlet valve and the outlet valve during a charge exchange, setting the residual exhaust-gas quantity in the combustion space at a second operating point in the compression-ignition mode as a function of a duration of the second outlet opening phase, and wherein the internal combustion engine is operated with spark ignition during a changeover from the first operating point to the second operating point, and vice versa.