An air-fuel ratio control device for an internal combustion engine can detect the deteriorated purification state of a catalyst without delay after completion of rich or lean control, and can rapidly restore the purification state. A filter process constant for a downstream O2 sensor output is set smaller...http://www.google.fr/patents/US7596941?utm_source=gb-gplus-shareBrevet US7596941 - Air-fuel ratio control device for internal combustion engine
Air-fuel ratio control device for internal combustion engine
