TROUBLE DIAGNOSIS APPARATUS FOR AN INTERNAL COMBUSTION ENGINE

摘要

A trouble diagnosis appartus comprises a cylinder internal pressure change detecting circuit to detect a change in the inner pressure of the cylinders of an internal combustion engine, a differentiation circuit to effect differentiation of an output signal outputted from the cylinder internal pressure change detecting circuit and a judging circuit to judge the internal combustion engine being faulty when a change quantity of output signal of the differentiation circuit is a predetermined value or lower.