Just had a 320d in today which is same engine as yours with exactly same fault apart from we only had a code for amm, after scoping and smoking could not find anything physically wrong, so with my apprentice holding the revs with the vehicle misfiring i got a screw diver and pushed open swirl valves and by magic fault dissapered i do beleive this maybe the fault with your if you have not already fixed it
hth
carl