| 摘要 |
An exhaust tract for an internal combustion engine of a motor vehicle includes a first exhaust gas line, which conducts exhaust gases from the internal combustion engine to an exhaust-gas treatment device, and a second exhaust gas line, which forms a bypass line bypassing the exhaust gas treatment device. In order to ensure sufficient treatment of the exhaust gas even in the lean operating mode of an internal combustion engine, at least one first valve and one second valve are provided in series in the bypass line. An exhaust line is provided between the first valve and the second valve to reduce the pressure between the first and second valves. The pressure upstream of the second valve and the pressure downstream of the second valve, or the ambient pressure of the motor vehicle, are determined and negative pressure is applied to the exhaust line such that an exhaust gas flow via the second valve to the outside into the environment of the motor vehicle is prevented. |
