FAILURE DIAGNOSTIC SYSTEM OF EXHAUST PRESSURE RISE DEVICE HAVING SUCTION PASSAGES, EXHAUST PASSAGES, EXHAUST PRESSURE RISE DEVICE, SUCTION SYSTEM PRESSURE DETECTION DEVICE, AND EXHAUST PRESSURE RISE FAILURE DETERMINATION PART

摘要

PURPOSE: A failure diagnostic system of an exhaust pressure rise device is provided to enable failure determination of the exhaust pressure rise device by utilizing a pressure sensor of a suction system. CONSTITUTION: A failure diagnostic system of an exhaust pressure rise device(40) has exhaust passages(13,14,20) and suction passages(9,10) communicating with a cylinder of an internal combustion engine(1), and the exhaust pressure rise device raising the exhaust system pressure of the corresponding exhaust passage. The failure diagnostic system has a suction system pressure detection device(3) arranged to the suction passage to detect the suction system pressure and an exhaust pressure rise failure determination part(51) determining a failure of the exhaust pressure rise device on the basis of the suction system pressure information by the corresponding suction pressure detection device and a failure determination reference range.