Method for determining light-off temperature and/or light-off performance in exhaust gas flow of internal combustion engine utilized in motor vehicle, involves calculating gradients of difference between model and measuring temperatures

摘要

The method involves determining measuring temperature (9) of exhaust gas flow downstream to a catalytic converter by a measuring element. Model temperature (11) is determined by a model for the measuring temperature. Difference between the model temperature and the measuring temperature is calculated. Gradients (17) of the difference are calculated. Light-off performance and/or light-off temperature of the catalytic converter is determined by the gradients. A falling flank (19) and/or zero crossover (21) of the gradients is determined. An independent claim is also included for a motor vehicle comprising an internal combustion engine of a catalytic converter.