| 摘要 |
The present invention relating to an EGR system diagnosing method includes the steps of measuring an EGR pressure value, which is a current EGR pressure value against the real amount of EGR gas introduced to an exhaust line, using an exhaust pressure sensor; when the target EGR pressure value exceeds the current EGR pressure value, determining whether knocking by adjusted ignition timing occurs by comparing a target EGR pressure value determined to response to a target EGR fluid; and delaying the ignition timing when knocking occurs, and diagnosing abnormality of an EGR cooler based on the delayed ignition timing by comparing the delayed time of the ignition timing and a predetermined maximum time for delaying an ignition timing. |
