Nitrogen oxide trap managing method for exhaust line of internal combustion engine of motor vehicle, involves determining quantity of sulfur in trap from measurement of carbon monoxide in gas at outlet of trap during regeneration of trap

摘要

The method involves temporarily increasing richness and temperature of a gas mixture that traverses a nitrogen oxide trap (9), for regenerating the trap by purging nitrogen oxide. Quantity of sulfur contained in the trap is determined from measurement of carbon monoxide present in gas at an outlet of the trap during the regeneration of the trap. The sulfur quantity is determined based on difference between a value of carbon monoxide measured at the starting of the trap regeneration and a value measured at the end of the trap regeneration. An independent claim is also included for a nitrogen oxide trap device mounted in an exhaust line of an internal combustion engine of a motor vehicle, comprising a sensor.