04 ls6 cylinder 4/5 missfiring

[flyboiz08]

i ran into this problem a couple days ago... my car accelerates slow... its loud.. its sounds like its a V8 so i took it to auto zone and ran it through the computer and my 4/5 cylinders are missfiring im thinkin a simple tune up will fix but im not really engine savy... any help is appreciated

thanks in advance for any help