| 摘要 |
<p>PROBLEM TO BE SOLVED: To recognize the deterioration of the absorber that absorbs the unburned hydrocarbon constituent when the catalyst is not activated, and prevent the release of desorbed hydrocarbons once the absorption limit has been reached. SOLUTION: Based on the knowledge that the absorber temperature and the exhaust gas temperature of downstream of the absorber are maintained during the absorption operation, an elapsed time tm.dtrs after the engine started is compared with a threshold value dtrs.lmt, and if it is lower than the threshold value, it is recognized that the absorber has deteriorated (S32). In addition, when the temperature tmp.trs exceeds the threshold value X.TRS.TLMT, the branch path (the by-pass exhaust path) in which the absorber is disposed is closed off (S34).</p> |
