A method and apparatus for controlling an air-to-fuel ratio of an internal combustion engine in which the air-to-fuel ratio is maintained within a predetermined control width or range even if one or more of the sensors which detect the conditions of the engine necessary to compute the desired air-to-fuel...http://www.google.fr/patents/US4462373?utm_source=gb-gplus-shareBrevet US4462373 - Air-to-fuel ratio control method and apparatus
