On board diagnostic system for motor vehicle IC engine

摘要

The diagnosis device is incorporated in a micro measuring rod for continuous measurement of the exhaust emissions of an automobile engine, with the measurement effected via IR gas absorption in an optical path without any moving parts. A number of parallel cells or vessels (10,14) have the exhaust gas fed through them simultaneously and are supplied with time-shifted light source pulses, with evaluation of the measuring data via a microprocessor using a quotient method, for storage via an internal RAM and an external memory card.