Remap and carbon clean

[And82]

I was wondering if anyone had any experience or recommendations for remaps for my 2.0tdi s-line cvt multitronic. It’s not great on mileage only get 40mpg’s, if that, on a good motorway run. It needs a bit more power it’s only like 140 when new but it’s got to move 3tonne of metal and my fat ***. The garage I found reomended an engine carbon clean but seems like a good idea. It’s got good service history and great to drive.