Ok, fresh update... My truck is now a lot better. Cause: 2 cracked plugs and pooched coils. Now it's only mildly fluctuating the boost as it was a long time ago.

 

I have had the same issue on my 2012 for some time now. I took it to my dealer and he said a code showed that cylinder #3 had a misfire. He cleared the code to see what would happen and sent me on my way. I was ok with that and told him I'd report back to see how things were going. As time went on I had a bad engine misfire at idle when engine was cold. After engine warms the misfire goes away. Also, during this time I noticed a noise like a loud flutter at times coming from somewhere but I can't pin point it. First, I thought it was a brake dragging but that is not it. Sounded like it is coming from engine compartment. It hasn't done this lately but misfire is still there on idle.

I took it back to the dealer 2 weeks ago and he hooked it up to computer and there are no codes that show up. He ordered a new coil and plug for the misfire. I believe plug and coil replacement will solve the misfire but not the turbo spooling problem. He is also going to do the intercooler update when all parts are in.

I will post what I find out.