N'ozuzu, injinia mgbagha nke mmanụ ụgbọala nzaghachi akara usoro na-ekpebi na oxygen ihe mmetụta dị nso na combustion ụlọ, na elu nke ziri ezi nke mmanụ ụgbọala akara bụ, bụ nke tumadi kpebisiri ike na e ji mara iyuzucha ikuku eruba, dị ka gas ọsọ. ogologo nke ọwa (gas na-adaba n'azụ ozugbo) na oge nzaghachi nke ihe mmetụta, wdg. Ọtụtụ ndị na-emepụta ihe na-etinye ihe mmetụta oxygen n'okpuru ihe mkpuchi ọ bụla nke cylinder ọ bụla, nke mere na ọ nwere ike ikpebi nke cylinder nwere nsogbu, nke. na-ewepụ ohere nke njehie nchoputa, na n'ọtụtụ ọnọdụ na-ebelata oge nchoputa site n'iwepụ ma ọ dịkarịa ala ọkara nke cylinders nwere nsogbu.Ihe ntụgharị catalytic nkịtị nwere ihe mmetụta ikuku oxygen abụọ yana sistemụ njikwa nzaghachi mmanụ ụgbọala nke na-ejikwa sistemu nkesa mmanụ ọkụ nwere ike hụ na mgbanwe kacha dịrị nchebe nke ihe ndị na-ekpochapụ ihe na-emerụ ahụ n'ime carbon oxide na mmiri vapor na-adịghị emerụ ahụ.Otú ọ dị, ihe ntụgharị catalytic ga-emebi n'ihi oke ọkụ (n'ihi ọkụ ọkụ na-adịghị mma, wdg), nke ga-eduga na mbelata elu nke ihe na-eme ka ọkpụkpụ na nkwụsị nke metal orifice, nke abụọ ga-emebi ihe ntụgharị catalytic kpamkpam.

Mgbe ihe na-eme ka ọ daa, anyị nwere ike ịma na ndị ọkachamara dị oke mkpa n'imezi gburugburu ebe obibi na ikpochapụ usoro.

Ọdịdị nke OBD-II nchoputa usoro na-eme ka on-board nlekota usoro na OBD-II nlekota usoro nke gburugburu ebe obibi na catalyst ezi nchọpụta pụtara dị ka ọxịdashọn e ji mara mma ma ọ bụ ọjọọ catalysts.Na arụ ọrụ kwụsiri ike, mgbanwe mgbaàmà nke ezigbo ihe mmetụta oxygen (na-ekpo ọkụ) n'azụ onye na-eme ihe kwesịrị ịdị obere karịa nke ihe mmetụta oxygen ọ bụla dị n'ihu onye na-emepụta ihe, n'ihi na onye na-arụ ọrụ na-arụ ọrụ na-eri ike mgbe ọ na-atụgharị hydrocarbons na carbon monoxide, nke na-ebelata ngbanwe mgbaàmà nke ihe mmetụta post-oxygen.