Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: markseth on 24 January 2008, 09:45:23

Title: 2.5td very poor fuel consumption please can anyone
Post by: markseth on 24 January 2008, 09:45:23
hi,im new to this site but finding it very fascinating.got a 2.5td p reg auto estate,only getting 15-20 mpg,not booting it as cant afford to,changed oil,air and fuel filter.no obvious sign of fuel leek,car driving and gear changing smoothly my first omega and cant fault a thing except the fuel consumption.can anyone pleeeeeeeeeeeeze help :y :y
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: platty on 24 January 2008, 10:08:35
I found this when I first got my TD, but I had just gone from a petrol to a diesel and I was driving the omega like it was a petrol. Once I had got used to the diesel way, my economy got a lot better as my foot wasn't fastened to the floor all the time. I should think being an auto would make the consumption slightly worse than a manual, but not by a massive amount?

I can't think of any mechanical reasons as to why the consumption would be so low - if you have done the servicing as you described  :-/

Someone else might have some ideas though.
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Pitchfork on 24 January 2008, 11:06:39
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hi,im new to this site but finding it very fascinating.got a 2.5td p reg auto estate,only getting 15-20 mpg,not booting it as cant afford to,changed oil,air and fuel filter.no obvious sign of fuel leek,car driving and gear changing smoothly my first omega and cant fault a thing except the fuel consumption.can anyone pleeeeeeeeeeeeze help :y :y
Is this what happens to liquids in Wales?? :D
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 24 January 2008, 16:03:08
Is this what the computer tells you or what you have calculated, or both?

Round town, TD autos aren't economical, in fact they are awful.  On a good motorway run, you should be getting much better.
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Seth on 27 January 2008, 18:21:30
Orrite butty - so you reckon your TD is a bit of a guzzler!
TD Autos tend to be on the thirsty side, but check your driving technique - if you're doing stop/start urban runs, or generally shortish trips, you're not giving this beast a fair chance. You've got to get the car up to normal working temperature before making comparisons. Also, do you allow your motor to tick-over in traffic queues with the gear-shift still in the 'D' position - NEVER do this - shift to 'N' and let it idle. My manual-box TD regularly returns around the mid-30's per gallon.
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: The Barge Captain on 27 January 2008, 19:15:26
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TD autos aren't economical, in fact they are awful.  

Dear Lord.  They must be bad for a phrase like that to be used on this forum  :o
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Pitchfork on 27 January 2008, 19:54:02
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Orrite butty - so you reckon your TD is a bit of a guzzler!
TD Autos tend to be on the thirsty side, but check your driving technique - if you're doing stop/start urban runs, or generally shortish trips, you're not giving this beast a fair chance. You've got to get the car up to normal working temperature before making comparisons. Also, do you allow your motor to tick-over in traffic queues with the gear-shift still in the 'D' position - NEVER do this - shift to 'N' and let it idle. My manual-box TD regularly returns around the mid-30's per gallon.
Why??

I get in the region of 28mpg around town & 33 on a long run
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: theowletman on 27 January 2008, 19:58:18
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hi,im new to this site but finding it very fascinating.got a 2.5td p reg auto estate,only getting 15-20 mpg,not booting it as cant afford to,changed oil,air and fuel filter.no obvious sign of fuel leek,car driving and gear changing smoothly my first omega and cant fault a thing except the fuel consumption.can anyone pleeeeeeeeeeeeze help :y :y
The BMW sourced engine is a big one, and a 6 potter, you should be getting a bit more that 15 / 20 mpg though. Try a friendly MOT station and have an emissions check done, that should tell you if there is anything wrong, I used a manual one as a taxi back in 1995 and I got about 30mpg on mixed runs, town, motorway etc. Some of the other drivers had 2.0 petrol omegas at that time, the consumption was nearly the same for the petrols as it was for the dervs. Also are you using proper fuel, shell / bp/ esso etc and not Sainsbury's crappy City diesel, it does make a difference in my experience.
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: kbou55 on 27 January 2008, 20:55:24
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TD autos aren't economical, in fact they are awful.  

Dear Lord.  They must be bad for a phrase like that to be used on this forum  :o

TheBoy has spoken 8-) 8-)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Turk on 27 January 2008, 23:37:53
15-20mpg does seem a bit thirsty, if you're not lead footed.
My Auto 2.5td with 225k on the clock gives 30-32mpg on a 50-50 of city/A-Roads and my Manual, with 96k, gives 40-42mpg.
Best I've recently seen was with Cruise set at 65mph and I got 52mpg from London to L.A (Llanelli Area).
Worst I've seen was after a few days of A-Roads and "Nose to Tail" city driving, Crimbo week a few years ago, and that showed 26mpg.
 
Let's be fair folks... a 1.7 tonne, 2.5 litre automatic that gives around 30mpg.  How can that be "Awful" ?
(Oh Lordy, "He" is bound to kick off now !)  
 
  
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 28 January 2008, 18:03:33
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15-20mpg does seem a bit thirsty, if you're not lead footed.
My Auto 2.5td with 225k on the clock gives 30-32mpg on a 50-50 of city/A-Roads and my Manual, with 96k, gives 40-42mpg.
Best I've recently seen was with Cruise set at 65mph and I got 52mpg from London to L.A (Llanelli Area).
Worst I've seen was after a few days of A-Roads and "Nose to Tail" city driving, Crimbo week a few years ago, and that showed 26mpg.
 
Let's be fair folks... a 1.7 tonne, 2.5 litre automatic that gives around 30mpg.  How can that be "Awful" ?
(Oh Lordy, "He" is bound to kick off now !)  
 
  
When you can get similar out of a v6, and lets face it, a v6 is so much more refined, handles better, bucket loads more power, easier to drive, and petrol is so much cheaper. Plus a V6 doesn't need its oil changed so often.
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: platty on 28 January 2008, 18:30:48
I would agree with TheBoy as he only said they are "awful" around town which is the truth in my experience, once you get going the economy is fine.

I haven't reset my MID yet this year and it shows 33.7 mpg and I do a 40/60 mix of short journey to long hauls. I'm happy with that. :)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 28 January 2008, 19:58:22
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I would agree with TheBoy as he only said they are "awful" around town which is the truth in my experience, once you get going the economy is fine.

I haven't reset my MID yet this year and it shows 33.7 mpg and I do a 40/60 mix of short journey to long hauls. I'm happy with that. :)
My tractor is reading 36.8mpg, mostly crappy A roads to work and back, autobox locked in 3rd.

Last time it went to Nottingham, the range + odometer would have been more than 800miles.

Actually, may have a piccy somewhere ::)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Pitchfork on 28 January 2008, 21:29:41
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I would agree with TheBoy as he only said they are "awful" around town which is the truth in my experience, once you get going the economy is fine.

I haven't reset my MID yet this year and it shows 33.7 mpg and I do a 40/60 mix of short journey to long hauls. I'm happy with that. :)
My tractor is reading 36.8mpg, mostly crappy A roads to work and back, autobox locked in 3rd.

Last time it went to Nottingham, the range + odometer would have been more than 800miles.

Actually, may have a piccy somewhere ::)
Because I'm in the cheap seats with only a GLS, I calculate my MPG by pencil & paper at circa 33 on long runs over a period of time, so nearly 37 MPG on A roads makes me jealous!
What's the trick, did you sell your soul to the Devil at the crossroads??
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 28 January 2008, 21:31:11
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Quote
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I would agree with TheBoy as he only said they are "awful" around town which is the truth in my experience, once you get going the economy is fine.

I haven't reset my MID yet this year and it shows 33.7 mpg and I do a 40/60 mix of short journey to long hauls. I'm happy with that. :)
My tractor is reading 36.8mpg, mostly crappy A roads to work and back, autobox locked in 3rd.

Last time it went to Nottingham, the range + odometer would have been more than 800miles.

Actually, may have a piccy somewhere ::)
Because I'm in the cheap seats with only a GLS, I calculate my MPG by pencil & paper at circa 33 on long runs over a period of time, so nearly 37 MPG on A roads makes me jealous!
What's the trick, did you sell your soul to the Devil at the crossroads??
chip ;)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Pitchfork on 28 January 2008, 21:34:25
You did sell your soul then!
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 28 January 2008, 21:36:20
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Actually, may have a piccy somewhere ::)
Already had 120miles from this tank
(http://images.omegaowners.com/images/theboy/project_tb2/IMAGE_00029.jpg)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: zirk on 29 January 2008, 03:10:32
700 miles on the Range and youv'e already had 120 miles from the tank?, yea come on yourv'e Tech 2'd that for that reading!

Gonna have to buy one of those T2, save a fortune on fuel! ;D
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: DJ Pete on 29 January 2008, 11:29:15
That's amazing, I've never seen my range go above 320
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: platty on 29 January 2008, 13:14:56
The most I have had on my range is about 600, but that is with a full tank and no miles under my belt. I am hoping that once I get a chip my economy will improve, but I'm not too fussed.

I won't worry about economy for the first couple of tanks after chipping!  :)
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: TheBoy on 29 January 2008, 21:39:33
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700 miles on the Range and youv'e already had 120 miles from the tank?, yea come on yourv'e Tech 2'd that for that reading!

Gonna have to buy one of those T2, save a fortune on fuel! ;D
I had just done 50 odd miles at a constant 70....
Title: Re: 2.5td very poor fuel consumption please can anyone
Post by: Pitchfork on 30 January 2008, 11:02:39
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Quote
700 miles on the Range and youv'e already had 120 miles from the tank?, yea come on yourv'e Tech 2'd that for that reading!

Gonna have to buy one of those T2, save a fortune on fuel! ;D
I had just done 50 odd miles at a constant 70....
That's 50 miles from the crossroads where he bartered his soul! ;D