Nasserk

I have 2006 A4 Quattro 2.0T that I bought about 4 month ago with a 120k miles on it, I noticed a misfiring problems on #3 cylinder and I went ahead and changed all 4 coils and check all spark plug on the way and they all looked good with a very small white ash that was stuck on them and knock all of it off very easily with a soft brush and installed them back. Now all the codes are clear.

But now I noticed another problem that it was hiding from me with the misfiring. Now I can hear a pops or small explosions coming from what it sound to me like from the turbo side of the engine, it only pops when I gun it on a dead start or low RPM, it will not do it when the car is rolling and engine at around 3k.
It sound to me like there is an excessive amount of unburnt fuel that is burning outside of the engine. Buy the way my engine sounds like a diesel engine on idling if that had anything to do with it??
Any one have any ida of why this is happing and what to test or fix this issue.
Thanks.