A method for operating a piston engine, in particular an internal combustion engine, wherein - the piston engine has - a number of cylinders (A1 - An, B1 - Bn), and - a crankshaft mounted using bearing journals in main bearings, which furthermore has a number of cranks and shaft journals in alternating sequence between the bearing journals, wherein - the crankshaft converts a movement of at least one piston in a cylinder of the number of cylinders (A1 - An, B1 - Bn) with load absorption by at least one connecting rod attached to one of the cranks of the crankshaft into a rotational movement, and - the crankshaft experiences a deformation and/or tension causing torsion due to the load absorption, and - the piston engine furthermore has a torque sensor system, assigned to the crankshaft, having at least one first and one second rotational angle sensor (S1, S2), wherein in the method - the first and the second rotational angle sensor (S1, S2) are magnetosensitive sensors and are part of a number of rotational angle sensors (S1, S2,..., Sn) spaced apart from one another and measure a first and a second rotational angle of the torsion directly from the crankshaft in such a way that the first and second rotational angle sensor are spaced apart from one another over a distance range of the crankshaft, wherein the first and second rotational angle are measured in the distance range, and - an angular offset between the first and second rotational angle (S1, S2) is determined, which results from the torsion of the load-subjected crankshaft, characterized in that - the distance range between the first and second rotational angle sensor along the crankshaft is restricted to a partial range of the distance between the bearing journals, and - the partial range comprises a subgroup of the number of cranks and/or shaft journals, so that the angular offset is to be assigned to the subgroup of the number of cranks and shaft journals, wherein - the distance range is restricted to - at least one shaft journal range, comprising at least one shaft journal between a first and a second crank, and/or - at least one crank range, comprising at least one crank, such that - the angular offset can be assigned to the at least one shaft journal and/or the at least one crank. - the piston engine has - a number of cylinders (A1 - An, B1 - Bn), and - a crankshaft mounted using bearing journals in main bearings, which furthermore has a number of cranks and shaft journals in alternating sequence between the bearing journals, wherein - the crankshaft converts a movement of at least one piston in a cylinder of the number of cylinders (A1 - An, B1 - Bn) with load absorption by at least one connecting rod attached to one of the cranks of the crankshaft into a rotational movement, and - the crankshaft experiences a deformation and/or tension causing torsion due to the load absorption, and - the piston engine furthermore has a torque sensor system, assigned to the crankshaft, having at least one first and one second rotational angle sensor (S1, S2), wherein in the method - the first and the second rotational angle sensor (S1, S2) are magnetosensitive sensors and are part of a number of rotational angle sensors (S1, S2,..., Sn) spaced apart from one another and measure a first and a second rotational angle of the torsion directly from the crankshaft in such a way that the first and second rotational angle sensor are spaced apart from one another over a distance range of the crankshaft, wherein the first and second rotational angle are measured in the distance range, and - an angular offset between the first and second rotational angle (S1, S2) is determined, which results from the torsion of the load-subjected crankshaft, characterized in that - the distance range between the first and second rotational angle sensor along the crankshaft is restricted to a partial range of the distance between the bearing journals, and - the partial range comprises a subgroup of the number of cranks and/or shaft journals, so that the angular offset is to be assigned to the subgroup of the number of cranks and shaft journals, wherein - the distance range is restricted to - at least one shaft journal range, comprising at least one shaft journal between a first and a second crank, and/or - at least one crank range, comprising at least one crank, such that - the angular offset can be assigned to the at least one shaft journal and/or the at least one crank.