Method and device for diagnosis of a particle filter arranged in the exhaust gas system of a petrol-operated internal combustion engine

A method for determining a presence of a correct particle filter in an exhaust gas tract of a petrol-operated internal combustion engine, the method comprising:

• determining with a control unit a measured differential pressure curve from a first pressure curve measured in the exhaust gas tract using a first pressure sensor arranged upstream of an installation position of a particle filter, and a second pressure curve measured in the exhaust gas tract using a second pressure sensor arranged downstream of the installation position;
• determining with the control unit a first result curve with a first low-pass filtration of the measured differential pressure curve;
• determining with the control unit a second result curve with a second low-pass filtration of the first result curve;
• determining with the control unit a first differential result curve by forming a difference between the first result curve and the second result curve;
• determining with the control unit a first amount result curve by forming an amount of the first differential result curve;
• determining with the control unit an expected differential pressure curve;
• determining with the control unit a third result curve with a first low-pass filtration of the expected differential pressure curve;
• determining with the control unit a fourth result curve with a second-low-pass filtration of the third result curve;
• determining with the control unit a second differential result curve by forming a difference between the third result curve and the fourth result curve;
• determining with the control unit a second amount result curve by forming an amount of the second differential result curve;
• integrating the first amount result curve into a first sum result and the second amount result curve into a second sum result when a first threshold value is exceeded by at least one of the third result curve, the fourth result curve, and the second amount result curve;
• evaluating with the control unit the first sum result and the second sum result to determine the presence of the correct particle filter.