How big is the pipe is it small bore inside or large bore?some times
you can get away with useing a plastic peice of pipe and a bit of
washer bottle pipe, as it is only a  b reather

Going by your figures of 60ltr I make that about 13.1 gallons uk, which
works out as about 34mpg, which I would say is pretty bad,
My 2.0 hdi van loaded up does around 48mpg
But again most of this is "A" road driving.
How much of your driving is sitting around in traffic? and what sort of
average speeds are you doing?
If your mate is getting 450 miles for 40 ltrs that works out as 8.8 gallons
uk then I think he is pulling your leg especially if you say he's driving
like a nutter as his works out at 51 MPG , no chance I think to that one.

GGJ

We have had our 05 reg 2.0 HDI since new - and havnt really been
getting that good fuel economy from the thing.

A fill up is now costing us £55 for 60 odd litres for a full tank -
and we barely manage to get 450 miles to the 60 litres!!

Surely for a diesel - this is wrong?  My m8 in his 1.6 astra nutter
sporty car - gets more than that on 40 lites and he drives like a
maniac!

Anyway - dont suppose anyone knows any reason that could cause this?

My next question is that on our little 106 - theres some kind of
breather connection to the air filter?  the air filter end of the tube
is broken - i nknow they are only a few pounds - but can i find
anywhere that sells them???  Nope - and im reluctant to pay a garage
£80 for something that costs less than a £5!!!

Anyway any help appreciated and thank you very much for taking the
time to read this!