My old 12.7 would create more boost any time it started up a incline, or small bump. You gave a VGT turbo. It's just the nature of the beast. Even at idle around 900 rpm no load but A.C. I would be showing 6 lbs of boost. Which really made me mad.
you your engine has two vpods. one of them is for turbo vans and it is malfunctioning(pressure goes up end down).