Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: georgie on 02 April 2010, 10:27:26

Title: 2.5td fuel economy
Post by: georgie on 02 April 2010, 10:27:26
I get 32 mpg on the OBC from an 98 CDX 2.5 td Estate auto. Its done 175k miles and is in good nick only the occasional puf of black smoke when accelarating. It passes emissions tests for the MOT. Is it possible to decrease consumption?
I am considering recon injectors and maybe a chip.
Does anyone have any suggestions or comments.
Many thanks
Title: Re: 2.5td fuel economy
Post by: Seth on 02 April 2010, 10:37:05
The only accurate method of calculating fuel consumption is to brim the tank, use it, then re-brim.

My previous chipped manual-boxed TD returned 33mpg running locally around here - proven!

If you want to chip an auto, you'll need to exchange your 'box for an AR35 version.
When chipped, the 'standard-fit' AR25 will quickly go into meltdown.
Increased torque and all that!
 :y
Title: Re: 2.5td fuel economy
Post by: TheBoy on 02 April 2010, 11:29:25
Thats probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (overread by around 10% as a guess).
Title: Re: 2.5td fuel economy
Post by: MickAP on 02 April 2010, 11:48:05
If you're getting 33mpg just runing local journeys then that's pretty good for the auto TD.
But if that's on longer say m/way cruising then yes I reckon it can be improved with some TLC somewhere. :y

Mick ;)
Title: Re: 2.5td fuel economy
Post by: hoofing it on 02 April 2010, 15:39:26
Quote
I get 32 mpg on the OBC from an 98 CDX 2.5 td Estate auto. Its done 175k miles and is in good nick only the occasional puf of black smoke when accelarating. It passes emissions tests for the MOT. Is it possible to decrease consumption?
I am considering recon injectors and maybe a chip.
Does anyone have any suggestions or comments.
Many thanks
It can be done but it's not worth it.it won't run well (under powered).
33mpg is good im only getting 25 (new pump en-route).
Why not clean the injectors yourself and save a fortune takes around 2 hours.
Title: Re: 2.5td fuel economy
Post by: Shackeng on 02 April 2010, 17:51:32
Quote
Thats probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (overread by around 10% as a guess).

Chipping mine definitely reduced my MPG by about 10%, but as you say the computer says it is better - it lies!
Title: Re: 2.5td fuel economy
Post by: MickAP on 02 April 2010, 19:40:02
Quote
Quote
That's probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (over read by around 10% as a guess).

Chipping mine definitely reduced my MPG by about 10%, but as you say the computer says it is better - it lies!

Yes definitely here as well, also clouds of black smoke from exhaust when I booted it, well more than should be.
Anyway chip removed....better mpg, smoke almost  unnoticeable. Back to normal, slug like acceleration :(
Apparently I may have had the wrong chip, so will investigate that one :y

Mick ;)
Title: Re: 2.5td fuel economy
Post by: Seth on 02 April 2010, 21:13:42
Quote
Quote
Quote
That's probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (over read by around 10% as a guess).
Chipping mine definitely reduced my MPG by about 10%, but as you say the computer says it is better - it lies!

Yes definitely here as well, also clouds of black smoke from exhaust when I booted it, well more than should be.
Anyway chip removed....better mpg, smoke almost  unnoticeable. Back to normal, slug like acceleration :(
Apparently I may have had the wrong chip, so will investigate that one :y

Mick ;)

Can you let us know the outcome Mick?
My previous tractor suffered similarly, and as I'll still be maintaining it, I'd like to effect a cure too!
 :y
Title: Re: 2.5td fuel economy
Post by: Shackeng on 02 April 2010, 22:32:10
Quote
Quote
Quote
That's probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (over read by around 10% as a guess).

Chipping mine definitely reduced my MPG by about 10%, but as you say the computer says it is better - it lies!

Yes definitely here as well, also clouds of black smoke from exhaust when I booted it, well more than should be.
Anyway chip removed....better mpg, smoke almost  unnoticeable. Back to normal, slug like acceleration :(
Apparently I may have had the wrong chip, so will investigate that one :y

Mick ;)

I don't suffer from that, just slightly on hard accel., and even that has reduced since giving it the 'diesel magic' treatment. :y
Title: Re: 2.5td fuel economy
Post by: tunnie on 02 April 2010, 22:40:13
try couple of tanks of BP fuel or Shell, supermarket fuel really does make diesels smoke
Title: Re: 2.5td fuel economy
Post by: MickAP on 03 April 2010, 02:14:57
Quote
Quote
Quote
Quote
That's probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (over read by around 10% as a guess).
Chipping mine definitely reduced my MPG by about 10%, but as you say the computer says it is better - it lies!

Yes definitely here as well, also clouds of black smoke from exhaust when I booted it, well more than should be.
Anyway chip removed....better mpg, smoke almost  unnoticeable. Back to normal, slug like acceleration :(
Apparently I may have had the wrong chip, so will investigate that one :y

Mick ;)

Can you let us know the outcome Mick?
My previous tractor suffered similarly, and as I'll still be maintaining it, I'd like to effect a cure too!
 :y

Will do :y
But for the time being I'm just going to see how it copes with the caravan in tow, without the chip.
It was great for towing with the other chip fitted, but mpg suffered, low 20's if I pushed it.
Returned to normal I should expect around 28 ish, will see next week :y

Mick ;)
Title: Re: 2.5td fuel economy
Post by: georgie on 13 April 2010, 10:54:16
Quote
The only accurate method of calculating fuel consumption is to brim the tank, use it, then re-brim.

My previous chipped manual-boxed TD returned 33mpg running locally around here - proven!

If you want to chip an auto, you'll need to exchange your 'box for an AR35 version.
When chipped, the 'standard-fit' AR25 will quickly go into meltdown.
Increased torque and all that!
 :y
How difficult is the Ar 35 swap? I presume that they are different in size and length, that would mean mountings propshaft swap etc. As much detail as you can manage would be great.
Title: Re: 2.5td fuel economy
Post by: georgie on 13 April 2010, 10:57:45
Quote
Thats probably around the right MPG for a TD tractor auto on a combined cycle.  Chipping, in my experience, upped MPG by around 15% (actual), but made the FC inaccurate (overread by around 10% as a guess).
What chip got you the 15% increase in miles/? There are some on ebay, but need to make sure that I buy the apple not the pear!
Title: Re: 2.5td fuel economy
Post by: PC Techy on 13 April 2010, 12:02:01
currently avg low 30's local, low 40's on a run with a powerbox fitted. Plenty of grunt and no smoke.
Title: Re: 2.5td fuel economy
Post by: georgie on 13 April 2010, 12:33:03
What make "powerbox" also where are they sold, ebay?
Title: Re: 2.5td fuel economy
Post by: PC Techy on 13 April 2010, 13:03:51
Box came from a company in germany MAL electonics, Just connects to 4 cables in the main ecu plug. Fully adjustable from normal power to 30% power increase.
http://www.mal-electronics.com/html/englisch.html

It's listed as td powerbox, only took 2 days to arrive from germany aswell.
Title: Re: 2.5td fuel economy
Post by: hoofing it on 13 April 2010, 13:15:54
Quote
Quote
The only accurate method of calculating fuel consumption is to brim the tank, use it, then re-brim.

My previous chipped manual-boxed TD returned 33mpg running locally around here - proven!

If you want to chip an auto, you'll need to exchange your 'box for an AR35 version.
When chipped, the 'standard-fit' AR25 will quickly go into meltdown.
Increased torque and all that!
 :y
How difficult is the Ar 35 swap? I presume that they are different in size and length, that would mean mountings propshaft swap etc. As much detail as you can manage would be great.
straight swap mind to use the ar35 tc
Title: Re: 2.5td fuel economy
Post by: hoofing it on 13 April 2010, 13:23:09
Quote
Box came from a company in germany MAL electonics, Just connects to 4 cables in the main ecu plug. Fully adjustable from normal power to 30% power increase.
http://www.mal-electronics.com/html/englisch.html

It's listed as td powerbox, only took 2 days to arrive from germany aswell.
is your car a auto or manual. if auto make sure its got a AR35 fitted going by the nm the Ar25 will destroy itself.

Title: Re: 2.5td fuel economy
Post by: PC Techy on 13 April 2010, 14:04:14
its manual, so no worries
Title: Re: 2.5td fuel economy
Post by: georgie on 13 April 2010, 16:18:57
So the AR25 and AR35 are identical appart from their innards??
If I buy one I just want to make make sure that I rip out all the extra bits(if any that are needed) from the scrapper
Also what mileage is too high for an AR 35. I know it depends on usage and misusage but any opinions would help.
Title: Re: 2.5td fuel economy
Post by: hoofing it on 13 April 2010, 16:27:38
Quote
So the AR25 and AR35 are identical appart from their innards??
If I buy one I just want to make make sure that I rip out all the extra bits(if any that are needed) from the scrapper
Also what mileage is too high for an AR 35. I know it depends on usage and misusage but any opinions would help.
mainly the torque convertor :y
Title: Re: 2.5td fuel economy
Post by: Omegatoy on 13 April 2010, 19:41:21
you need to use the td bellhousing and the torque converter!!