DETERIORATION DETECTOR FOR CATALYST

摘要

PROBLEM TO BE SOLVED: To obtain a deterioration detector catalyst in which the extent of deterioration can be determined for catalytic converter without relying upon the O2 storage capacity. SOLUTION: A catalytic converter 1 and a first oxygen sensor 2 are arranged in the exhaust system of an internal combustion engine. A second oxygen sensor 3 having reduced oxidizing/reducing capacity at the detecting part thereof is arranged on the downstream side of catalytic converter in an exhaust system. Means 10 determines the extent of deterioration of catalytic converter by comparing the outputs from first and second oxygen sensors or the values based thereon each other.