Fuel injection control arrangement for internal combustion engine with abnormality detection function therein

摘要

A control arrangement for an internal combustion engine which includes a fuel supply system, an air/fuel ratio control system, an abnormality diagnoser which diagnoses a possible abnormality in the fuel supply system, when the pressure of the pressurized fuel in the fuel supply system detected by a fuel pressure senor exceeds predetermined upper and lower limits determined by a control duty for an electrically controlled pressure regulator, and an abnormal element decider which decides an abnormality either in the fuel pressure sensor or in the electrically controlled pressure regulator based on an amount representing an air/fuel ratio status including the actual air/fuel ratio and the air/fuel ratio feed back control amount extracted from the air/fuel ratio control system for the internal combustion engine, when the abnormality diagnoser diagnoses an abnormality in the fuel supply system.