Fuel Consumption

[bbg404]

I bet every one is sick of seeing this title but its starting to get to me now!!

I haven't posted or read on here for a few month now as I've just been using my 130 as a car and haven't really had time to think about messing round with the car

But I've only been averaging low 40s on the mpg front since I got the car!! The day I had it fix and ready to use it was serviced by a VW specialist garage who changed everything as it was only on 50k miles and wasn't sure when it was last serviced!! But I bought this car for economy

The only thing I can think of is when I put my foot down there's a whistle maybe like a turbo pipe

Any one got any ideas what I could change to help this??

The cars totally standard but been thinking of a map

Cheers