Poor winter fuel economy

[Tony]

The Largo is definitely drinking it at an alarming rate. Will 2-ehn help or am I better off thinning with petrol to aid atomisation?

[greasemonkey]

The question is, is it a fault, or the fuel? It could be a fault with the vehicle it self.

[Tony]

No obvious drips from underneath, really I need to whip the driver's seat out and check the leak off rail isn't leaking... off.

[greasemonkey]

I wasn't thinking so much of it running out somewhere, although that is a possibility.
Is there some kind of electric trickery gone awol, that makes it think it's mega cold, so is pumping more fuel through? Cold start not turning itself off?
Would it be doing the same if it was on pump diesel?
Is there a brake dragging? It's automatic, innit? You could easy have one of the drum brakes at the back dragging (or even a disc) which may well not be noticeable in driving, but could add significantly to the fuel consumption.
Anyone pulled the handbrake up lately? Do you mostly use the park position on the shift lever mostly?

Just thinking out loud really, but I'd hesitate to pin it on the bio just yet.

[Tony]

I wasn't thinking so much of it running out somewhere, although that is a possibility.
Is there some kind of electric trickery gone awol, that makes it think it's mega cold, so is pumping more fuel through? Cold start not turning itself off?
Would it be doing the same if it was on pump diesel?
Is there a brake dragging? It's automatic, innit? You could easy have one of the drum brakes at the back dragging (or even a disc) which may well not be noticeable in driving, but could add significantly to the fuel consumption.
Anyone pulled the handbrake up lately? Do you mostly use the park position on the shift lever mostly?

Just thinking out loud really, but I'd hesitate to pin it on the bio just yet.

Yes it's auto, and I always use the handbrake - though the handbrake is actually a ratchet operated foot pedal with a release handle underneath the dash.  I'm pretty sure nothing is binding as it rolls just fine in neutral.

I have messed with the fuel temperature sensor though to report a higher fuel temp than normal - this was to increase fuelling at idle to prevent a stall problem, with the added side effect of increasing engine power.  This didn't seem to affect fuel economy at all over the summer months - but perhaps now it is causing a problem?  Certainly when driving I've noticed the ECU selecting a high idle until things get warm - enough to run the car along at 20mph without pressing the accelerator.

[Tony]

Now this is interesting on 2-EHN:

http://www.fragging.de/2EHN.pdf

This effect is greatest at lower temperature-density conditions, corresponding to low-load and start-up conditions in a diesel engine, and becomes negligible at the highest temperature-density conditions examined.

This paper strongly suggests that 2-EHN has the greatest effect on short, cold started journeys and not to long, hot journeys, which might explain the variable results we've seen reported on the forums.  Since cold short journeys are what I mostly do, I've got some 2-EHN on order to see how it goes.

[Jamesrl]

From personal experience I can't agree with the above statement ref 2-ehn and hot running, yes it's good for cold starts but I get an 8/9% improvement on mpg over not using it for long runs.

[Tony]

Interesting.  What ratio are you dosing?  1:1000 or slightly stronger?

[1958steveflying]

Where are you guys buying it from ?

[Tony]

Trinity, £13 for 1l delivered.

http://www.ebay.co.uk/itm/231410380937  (I offered £13 and it was automatically accepted).

[1958steveflying]

Cheers Tony, I'm just about out of all additives now !

[nigelb]

Where are you guys buying it from ?

Better value can be found here:

http://www.ebay.co.uk/itm/2-EHN-Highest-quality-99-9-pure-2-Ethyl-Hexyl-Nitrate-Cetane-Booster-5-Litres-/201078885372?pt=LH_DefaultDomain_3&hash=item2ed13c4bfc

£9 per litre represents good value in my book

[GedsJeep]

just for info...

this..

http://www.chemiphase.co.uk/fuelforce-2000-petroleum-diesel-performance-enhancer/

contains no 2-ehn.

[nigelb]

just for info...

this..

http://www.chemiphase.co.uk/fuelforce-2000-petroleum-diesel-performance-enhancer/

contains no 2-ehn.

...but that's not for bio....it's for dino.

No idea what's in it...or indeed, what's not in it.

[GedsJeep]

me either, but it has been bandied around on vod as 2-ehn.

this is from chemiphase (just up the road from me...)

Dear Sir,

 

We do not supply 2EHN

But we have a product fuel force 2000 which contains several fuel additives, and also contains mixed EHN, type components,

What fuel type are you planning to use this product for and at what concentration,

Does the fuel you intend to treat, have a low cetane number ?

Clive