2006 Avalon sputtering

[tlane276]

Car started sputtering at idle and when accelerating. Got codes pulled and came out w a bunch. MAS (I replaced)...ignition coil...misfire on 3 and 6 (changed coil for 6 and all 3 plugs in front, the rear 3 plugs and #3 coil are this weekend). After replacing the MAS and the coil and 3 plugs in front, car still sputters. I think it is getting worse. Can 1 bag ignition coil and plug cause it to sputter so badly? Can my cat be clogged even though I didnt get a code for it? Im hopin that changing the #3 coil and putting all new plugs in the back 3 cylinders will fix it but for some reason....I am not too optimistic. Anyone have and advice?