Cm870 demandated hot egts

[Upnorth83]

I’m still struggling with this engine tune. I’m working on purchasing Cal?erm so I can copy the tune out. I put a {aftermarket} twin oil cooler on it and oil temp runs around 210 now gets up to 225 on the hills. I thought it was going good. Then as the weather has cooled off in the last two weeks my boost has started jumping all over. Up and down. I had a copy of insite on my computer but it has disappeared. So I am working on getting that back as well. When check engine comes on it derates and sucks the life out of it. When I’m pulling and the engine light starts flashing off I lift my foot and go back in to it everything smooths out for a minute boost jumps to 40 41 and everything gets smooth and quite, lasts for about 3 seconds then boost falls off and back to noisy and no boost. I’m starting to think this truck is going to be the end of me. I had read on here that there is a flaw in Cummins programming that causes this issue. I’ve bought some resistors to try and fool it by bypassing the intake air temp sensor. I have load tested and replaced every sensor and wire. It has to be something in the tune right?