another mpg question

[bigjy]

hey peeps, ive got a 55 reg pre-facelift 1.9cdti (150), and im only getting 450-500 per tank, mostly motorway speeds at 70mph on cruise control, is this normal?, was expecting alot more?, thanks

[paul_sri150]

I usually get 600-700 at them kinds of speeds, but just put a new dtuk box on so hoping to get a little more

[bigjy]

thats what i thought i should ve been getting, any ideas on what to check?

[Mr Hyde]

Whip out air filter and check. My one was f'ing disgusting and clogged with leaves etc. Plus do the airbox mod at same time

[bigjy]

ive done that already mate and fitted a k&n filter, was minging with wasps etc etc

[Ginge7289]

serviced?

[Hideous]

automatic or manual? the autos are a bit thirsty
signum or vectra?

[bigjy]

its a vectra, manual, fuel filter was changed, 0nly at 34k so not due service till 40k

[Ginge7289]

Hmmmm, it does not sound right, If you do the speeds you are saying. I get 600 out of my 120 and it needs servicing. How do you drive it round town?

[bigjy]

i do 40 mile round trip to work, 36 mile on motorway rest, general speed limits, no much heavy right footing