INTERNAL COMBUSTION ENGINE CONTROLLING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a control device capable of precisely calculating an actual opening degree of an EGR valve with a simple constitution in an internal combustion engine having an EGR device.SOLUTION: The controlling device comprises: a throttle valve arranged in an intake passage; an EGR passage for connecting an upstream side of the throttle valve in the intake passage to an exhaust passage; the EGR valve arranged at a middle of the EGR passage; and an air flow meter for measuring signals corresponding to an intake flow rate or intake pressure on the upstream side of the throttle valve in the intake passage. When an opening degree of the throttle valve is smaller than a predetermined threshold, a pulsation waveform of signals of the air flow meter is measured, so as to calculate the actual opening degree of the EGR valve according to a degree of amplitude of the pulsation waveform. Preferably, when an engine rotation number is smaller than a predetermined rotation number, the pulsation waveform is measured.