From a previous post, you have more issues....
P2263 Code, and high EGTsI just had the same problem couple days ago. Once the cold hit my truck lost power and my boost was between 30-40 just driving normally. I changed the map sensor, the ebp sensor and tube. I probably could have cleaned them all but for peace of mind I just change everything. After I did that I cleared the code and truck runs better than before.
You may need to do some extra cleaning and checking. This could be the related to the low ICP voltage you are seeing. It would be very prudent to ensure the EBP sensor and tube are clear and working properly, as well as the MAP AND MAF sensors, especially given the level of corrosion and sticking in the old turbo. As well, ensure your VGT solenoid is working correctly. Of course, you could've have multiple issues as Tuscany suggested.