FAILURE DETECTOR OF INTERNAL COMBUSTION ENGINE

摘要

PURPOSE: To provide a failure detector of internal combustion engine capable of surely detecting the abnormality of an air flow sensor regardless of exhaust flow control. CONSTITUTION: This failure detector of internal combustion engine has a failure detection means (S22-S30) for detecting the abnormality of a new air flow rate detection means (air flow sensor) based on the comparison result of the new air inflow quantity detected by the new air flow rate detection means (air flow sensor) with a new air inflow quantity reference value set by a new air quantity reference value setting means (S20); and an exhaust flow rate adjusting device (exhaust flow rate adjusting means, target adjusting quantity setting means, and exhaust flow control means). The new air quantity reference value setting means sets the reference value (S16) according to not only the operating state of the internal combustion engine (engine speed Ne, fuel injection quantity Qf, etc.) but also the target adjusting quantity (target throttle valve opening) of the exhaust flow rate adjusting means set by the target adjusting quantity setting means (S12 and S14).