| 摘要 |
In an internal combustion engine, a catalyst (15) monitor includes a resistive type oxygen sensor (16) positioned between the engine (11) and the catalyst and a temperature sensor (20) positioned proximate to the catalyst. The oxygen sensor measures an oxygen concentration of the engine emissions and the temperature sensor monitors a temperature of the catalyst and detects a light off time of the catalyst. The magnitude of resistance of the oxygen sensor is measured and compared to a predetermined threshold level. The catalyst light off time is compared to a predetermined time value. In addition, a lifetime temperature profile of the catalyst is generated and compared to a predetermined threshold temperature level. The results of the comparisons are used to establish whether the catalyst is operating efficiently. <IMAGE> |
