Replaced second boost converter and double checked all the vacuum lines. I also checked that the waste gate was functioning correctly. Unluckily any replacement intercooler inlet hoses are on back order so IDK when I'll be able to replace that. I also replaced all seals/gaskets on the intake manifold this morning.

Still going into limp at 95mph under WOT.

Pulled codes and got 428b which is the boost pressure control, low-pressure stage, control deviation. Researching that seems to lead me toward vacuum (don't think there is an issue there) waste gate function (seems to work) and tune. I have Malone tune and I found issues from 2018-ish but nothing much after that. I had Whitbread install the tune December 2019. IDK if that was still a problem then or not.