**No sin can go into heaven otherwise sin would overtake heaven and God will not have that. Even one sin, not dealt with, would keep one from heaven.**
That’s why there is a purging place called Purgatory — so the souls can atone for the reparation they did not do on earth.
Sorry, without faith in Christ there is no remission of sins anywhere. After one dies, the next step is Judgement: "And just as it is appointed for man to die once, and after that comes judgment" Hebrews 9:27 and either faith in Christ justifies you clean or sin judges one dirty and liable.