APPARATUS FOR INDICATING THE DEGREE OF DIRTINESS OF A FILTER

摘要

An apparatus for indicating the extent to which an air filter in an internal combustion engine is fouled. For this purpose the apparatus includes a pressure sensor, a sensor to detect the rotational speed of the engine, and an additional sensor which determines the load state of the engine. The signals of the three sensors are combined and serve to produce an air filter dirtiness indicating signal.