I ka ʻōnaehana MPI, ua hoʻokaʻawale ʻia nā injectors i nā pūʻulu, a ua hoʻohuli ʻia nā injectors i ka hui like i ka manawa like. No ka laʻana, ua māhele ʻia nā mīkini pahu 4-cylinder i ʻelua mau pūʻulu, ʻo kēlā me kēia hui o ʻelua injectors, ʻo kēia mau pūʻulu ʻelua o ka injectors e hoʻololi i ka ʻaila ʻaila, ka crankshaft engine i kēlā me kēia huli aia kahi pūʻulu o nā injectors e pīpī i ka ʻaila. Hoʻohui like kēia ʻōnaehana o nā injectors, ʻo ka ECU wale nō ma ka hui like o nā injectors a pau e hoʻouna i ka hōʻailona like, aia nā injectors i ka manawa like e wehe a pani, maʻalahi ka polokalamu e hoʻomaʻamaʻa i ke kaapuni uila, akā. no nā kūlana like ʻole o ka ʻenekini nele i nā hoʻololi maʻamau i ka hana, e hoʻopuka i ke ʻano o ka stagnation o ka aila a me ke kinoea i loko o ka intake manifold.

ʻO ka ʻōnaehana SFI, kēlā me kēia injector pili pono i ka ECU, kēlā me kēia, hiki ke hana pololei ʻia ma mua o ka wehe ʻia ʻana o ka valve intake injector, hiki ke hana i ka injector ma waena o nā manawa injection ʻelua hoʻololi koke i ka hui ʻana e hoʻololi i nā loli i nā kūlana like ʻole. . No laila, ʻo SFI ke ala pololei loa a kūpono hoʻi o ka ʻōnaehana wahie hoʻokele uila uila, nui nā ʻenekini kaʻa e hoʻohana nei i kēia ala.