| abstract |
An exhaust purifying member (31) is located in annexhaust passage (26) of an internal combustion engine (1). Antemperature sensor (33) detects the temperature of exhaustngas at an exit of the exhaust purifying member. A diagnosisnmeans diagnoses the state of clogging of the exhaustnpurifying member based on an exhaust temperature that isndetected by the temperature sensor when the additive isnsupplied to the exhaust purifying member. Accordingly, thenclogging state of the exhaust purifying member is reliablyndiagnosed. |