| 摘要 |
A method is provided for detecting defective injectors for feeding fuel into the combustion chambers of an internal combustion engine, in particular in a motor vehicle, in which the internal combustion engine is operated in the idling mode with an idling rotational speed which is increased compared to the normal idling mode. The mixture control of the internal combustion engine is deactivated, by which control the mixture of fuel and air in the respective combustion chambers is adjusted in the normal operating mode of the internal combustion engine based on a characteristic value which depends on the ratio of air to fuel in the mixture and which is measured for one or more injection groups composed of a plurality of injectors of the internal combustion engine, in each case jointly for all the injectors of the injection group. In each case the following steps are carried out for at least some of the injection groups with activated measurement of the characteristic value: a) each injector of the respective injection group is switched off selectively, and the change in the characteristic value when the respective injector is switched off is detected; b) a fault criterion is checked, the fault criterion being satisfied when the change in the characteristic value for the respective, switched-off injector exceeds or undershoots a predetermined amount; c) if the fault criterion is satisfied a defect in the respective injector is detected. |
