hi
welcome to the forum
you dont get many visits in this section, you might get better responce from the a3 section .
what year a3 do you have ?
I had a 98 1.9 tdi a3 110 , had that remapped by jabbasport to 144 bhp
no problems at all
there are a few good tuners about , just keep to the well established ones and you should be fine.
revo , superchips , giac , custom code , apr , jabbasport , amd , jbs . . . . . .etc