Welcome!
The 01 ecu will not work in the 03 I'm afraid, ecu must be ME7.1.1 from 2003-2005 audi a6 or allroad to work in your car
I read your thread, are you saying it's requesting 1500-1600mb? Is that absolute, or boost? If it's boost, that's 20psi.
Oh shucks on the 01 ecu. yeah, that's absolute with 960 ambient, so we're talking 9-10psi:). I'd be happy little boy if it was boost. I have a lot of information to share, as I have been trying to figure this whole situation for a couple of months now. I think i've listed most of what I know in the audiworld thread, but perhaps with less detail.