I used to get around 54mpg in my vec oil burner but that's dropped down to about 30mpg now.

 

The only things I've done are clean the turbo sensor and put a can of 10k through it. The engine is running fine and it boosts as it should but the mpg is crap.

At first I thought it was the DPF but it should have recharged by now.

 

Oh, and I'm not being heavy on the right foot either.

 

Anyone have any ideas as whats going on?

When did you last change the filter?

I've never changed the DPF, it's supposed to recharge on it's own. Don't know if it has though?

Themostat?

Tyre pressure.

Oil/air filters....

 

My money is on the thermostat.

Stop trying to drive it like a z = instant 20 mpg lol

Themostat?

Tyre pressure.

Oil/air filters....

 

My money is on the thermostat.

 

What he said!

Change the DPF

Sounds silly but have you worked this out manually? Or are you taking the cars readings?

 

I doubt it will be so very wrong but its worth working it out properly so you know exactly what your dealing with.

 

I have the 120bhp engine of that in my astra, its done 71k now (i've had it from new) and has returned 44.9mpg over the last 71k (ive never reset it!) Now if I work it out manually its actually just over 45mpg but its very close. I do tend to drive at 85 or so everywhere, great these private roads that go to all my destinations! With a heavy foot and the back of the van full with boxes of cable, pumps computers etc. All fairly heavy.

 

Having reset the trip 2 computer about 38k ago as an experiement I drove sensibly for a weekend and it did 55mpg+ but I have read about the DPF getting blocked and it does say in the manual about it only cleaning >2000rpm when the engine is hot. Do you do many long journys at a higher engine speed?

Its a sign from the Gods.

 

They're telling you to ditch the Derv burner and use the Zed instead.

 

Only a fool would drive a diesel that does 30 mpg... (says the man who used to get even less from his Omega 2.5TD)

 

My mates Mondeo was doing chronic mpg - one of his turbo pipes was not fitted tightly enough and was leaking boost. Was a quick fix, it was obvious from all the soot in the engine bay that something was amiss.

probably killed the air flow meter with the 10k boost, these things always promise the world but they are terrible

Thanks for all the replies mates, I'll give the bugger a service and see if that helps.

 

I've tried swearing and shouting at it but it didn't help. lol

 

 

EDIT: just bought a new air filter and oil one for £11 posted on the bay, damn this vectra's expensive :lol:

Edited July 23, 201114 yr by Steams

I've tried swearing and shouting at it but it didn't help. lol

 

Hmmmmmmm im at a loss then......

Dont worry, I have a brand new Insignia diesel and its only managing 35 mpg, not the 54 that the dealer said I should be getting. Its been back seven times so far and had new tyres, brakes and brake discs after 4800 miles and is still no better. I think its just because its a Vauxhall ???