Hi,
Thanks for the reply.
It is completely standard with no mods.
It's a 2006 plate 5 door with only limited service history since it was a previous local authority/police owned car.
Cambelt and water pump changed two years ago.
It drove absolutely fine during my test drive with no warning lights but immediately after i filled the tank the warning light came on.
Possibly got a member on Scottish VW forum with VCDS willing to scan for error codes.