Good fuel economy
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- 2.0 HDI 110
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Good fuel economy
I suppose filling it up to the brim is the best way to judge how much diesel is left, but normally i just put £20 in the car and drive it until the trip computer says ---- to empty. At the worst of times its about 100 miles, but this week i got 205 miles on £20 of diesel,
the thing is if i use paper to work it out 205 miles on £20 of diesel priced at 1.419 is 14.09 litres which converts 3.099 gallons then i get 66mpg (which doesn't sound right), although the trip computer says 43.7mpg.
All these numbers are getting confusing, the car was definatley at ---- when filled the last time, in fact i drove about 10 miles on ---- before putting the fuel into the car. The only difference with the driving was that it had 2 long airport runs at 100 miles each. The air con was used a bit to demist the windows and the heated seats were on constantly
the thing is if i use paper to work it out 205 miles on £20 of diesel priced at 1.419 is 14.09 litres which converts 3.099 gallons then i get 66mpg (which doesn't sound right), although the trip computer says 43.7mpg.
All these numbers are getting confusing, the car was definatley at ---- when filled the last time, in fact i drove about 10 miles on ---- before putting the fuel into the car. The only difference with the driving was that it had 2 long airport runs at 100 miles each. The air con was used a bit to demist the windows and the heated seats were on constantly
- sirwiggum
- 3.0 24v
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Re: Good fuel economy
I used to get about 140 miles to the £20 in my 406.
In the Honda I get about 70.
Filled it up today, Tesco petrol 135.9p, cheapest I've seen it. Had a voucher from last weeks messages too, 5p off.
In the Honda I get about 70.
Filled it up today, Tesco petrol 135.9p, cheapest I've seen it. Had a voucher from last weeks messages too, 5p off.
- Doggy
- Mod with a 2.2 HDi, De-Fapped!
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Re: Good fuel economy
I've noticed an improvement in mine just recently too. Had been getting 39/40 ish, which I put down to excess enthusiasm,
and maybe lousy weather.
Last tankful, did a brim - brim check, 639.8 miles 66.3 litres = 43.8 mpg, (which agrees with the trip computer). I know this isnt record breaking stuff, but it's respectable given doggy's impatience).
Did the oil change etc last week. I think that helps too - fairly sure the old stuff's too thin to work the tappets properly beyond about 10k miles. It's certainly quieter, smoother and maybe a tad more pokey after a service.

Last tankful, did a brim - brim check, 639.8 miles 66.3 litres = 43.8 mpg, (which agrees with the trip computer). I know this isnt record breaking stuff, but it's respectable given doggy's impatience).

Did the oil change etc last week. I think that helps too - fairly sure the old stuff's too thin to work the tappets properly beyond about 10k miles. It's certainly quieter, smoother and maybe a tad more pokey after a service.
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
Re: Good fuel economy
i have same on my hdi 90 think isnt too badsirwiggum wrote:I used to get about 140 miles to the £20 in my 406.

Re: Good fuel economy
I remember the days when i could get 100 miles to a tenner in my old xsara... oh how times have changed it's more like £25 for 150 miles now....Whats going on at our pumps anyway? my local asda has dropped diesel by 10p per ltr in three weeks.
That means a might £7 saving to us 406 boys on a full top up..... Countrys going mad.

That means a might £7 saving to us 406 boys on a full top up..... Countrys going mad.


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- 2.0 HDI 110
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Re: Good fuel economy
I have also noticed this diesel a few weeks back was £1.45 at the cheapest place, now all of a sudden the most expensive garage is now the cheapest at £1.399. But i still got the message from fair fuel uk asking me to do another survey.
Re: Good fuel economy
Whats the score with it coming down so quickly? it cant be the government they'd be ramming it down our throats on the news every day making us know their saving us money. 

- Bailes1992
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Re: Good fuel economy
I got 100 miles to less than £13
HDi90 is fantastic to get good economy out of. You just hoof it between 2-3k to get upto speed and then when you upto speed just feather the throttle and cruise around the 2000rpm mark and at no point let it go under 1500rpm.

HDi90 is fantastic to get good economy out of. You just hoof it between 2-3k to get upto speed and then when you upto speed just feather the throttle and cruise around the 2000rpm mark and at no point let it go under 1500rpm.
2020 BMW 520d MSport Touring My Daily
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1996 Land Rover Defender 90 County SW 300TDi My Toy
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2017 Dacia Logan MCV 1.5DCi Laureate Wifes
1996 Land Rover Defender 90 County SW 300TDi My Toy
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Re: Good fuel economy
I took a run down to Griffin mill today for a handbrake sensor and noticed that the last time i went down the A470 by the time i got to upper boat i was doing over 60mpg (in December) today though i hit 54mpg max... i realise my back brakes have been sticking a bit but they must have cost quite a bit in fuel over the last few months.Bailes1992 wrote:I got 100 miles to less than £13![]()
HDi90 is fantastic to get good economy out of. You just hoof it between 2-3k to get upto speed and then when you upto speed just feather the throttle and cruise around the 2000rpm mark and at no point let it go under 1500rpm.
Plan has been to strip them down but i was told one of the rear calliper bolts (the square drive one) had been rounded off but looking at it today thats crap so i'm jacking it up tomorrow.
- CountryPug
- 2.0 Turbo
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Re: Good fuel economy
I've been taking an average since I got the 405 as I don't have one of these new-fangled trip computer thingys. I ran it to what I considered was dangerously low levels, needle consistently at the bottom of the lowest mark on the gauge. Each time I fill up I keep a note of the amount of litres I've put in. Then I run the car to this low point again, take the mileage and do the calculations. The 405 has been doing what I think is a pretty impressive 52mpg. I'd say my driving style is pretty relaxed, know I'm in an old car so try to stay out of the turbo range if I'm not in a hurry. I've also noticed an improvement since I put in a new air filter so this figure could increase another mpg or 2 


Present - 95' 405 GLX TD
Previous - 01' 406 LX HDi
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- 2.0 HDI 110
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Re: Good fuel economy
52 mpg is great, its the litres to gallons thing i find confusing, why don't we have miles per litres, or litres per 100 miles?
What does 205 miles on 14.09 litres work out at, is 3.099 divided by 205 the way to do it?
66mpg sounds almost too good, is my maths not working right?
About the hdi if it does actually run out, how bad is it?
What does 205 miles on 14.09 litres work out at, is 3.099 divided by 205 the way to do it?
66mpg sounds almost too good, is my maths not working right?
About the hdi if it does actually run out, how bad is it?
- Doggy
- Mod with a 2.2 HDi, De-Fapped!
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Re: Good fuel economy
1 gallon = 4.54 litres
If you run out, don't keep churning it over on the starter as this spins the HP pump with no lubricant, (fuel).
Bung some diesel in, turn the ignition on until the lift pump stops, repeat about 3 times, then fire her up.
(Unless you have a Siemens, in which case add diesel, then squeeze the primer bulb thingy repeatedly until it goes firm and/or RSI sets in).
If you run out, don't keep churning it over on the starter as this spins the HP pump with no lubricant, (fuel).
Bung some diesel in, turn the ignition on until the lift pump stops, repeat about 3 times, then fire her up.
(Unless you have a Siemens, in which case add diesel, then squeeze the primer bulb thingy repeatedly until it goes firm and/or RSI sets in).
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
- CountryPug
- 2.0 Turbo
- Posts: 466
- Joined: Mon Dec 29, 2008 5:33 pm
- Location: Northern Ireland
Re: Good fuel economy
Yeah I'm still amazed that an old 405 1.9 Turbo diesel saloon car is more economical to run than my newer 106 1.1 hatchback. It just goes to show
Nope, that all works out FarmerPug, that's REALLY good going
Emm I wouldn't think it'd be good for the lift pump, it needs the diesel to lubricate it, a few miles working with no fuel could seize it. I'm guessing there'd be a few miles in the fuel lines before you'd come to a stop. I put petrol in my old 406 HDi one time, fuel pump seized after a few miles, it didn't like it

Nope, that all works out FarmerPug, that's REALLY good going

Emm I wouldn't think it'd be good for the lift pump, it needs the diesel to lubricate it, a few miles working with no fuel could seize it. I'm guessing there'd be a few miles in the fuel lines before you'd come to a stop. I put petrol in my old 406 HDi one time, fuel pump seized after a few miles, it didn't like it


Present - 95' 405 GLX TD
Previous - 01' 406 LX HDi
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- 2.0 HDI 110
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Re: Good fuel economy
The 406 beats the clio 1.2 no problem its amazing how much further a big diesel can go than a small petrol on the same quantity of fuel. Its amazing though to hear of a 405 getting 52 mpg who needs a prius.CountryPug wrote:Yeah I'm still amazed that an old 405 1.9 Turbo diesel saloon car is more economical to run than my newer 106 1.1 hatchback. It just goes to show![]()
Nope, that all works out FarmerPug, that's REALLY good going![]()
Emm I wouldn't think it'd be good for the lift pump, it needs the diesel to lubricate it, a few miles working with no fuel could seize it. I'm guessing there'd be a few miles in the fuel lines before you'd come to a stop. I put petrol in my old 406 HDi one time, fuel pump seized after a few miles, it didn't like it
I think driving the car further helped, going from dungannon to the international airport is ok up the m1 but on both occasions i come home round the other side i.e. antrim, tome, money more direction, instead of back down the m1.
The lift pump is the one in the back seats, it wouldn't be so bad if it seized (apart from the price of a new one) if the High pressure pump on the engine seized would it snap the timing belt?
- Bailes1992
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Re: Good fuel economy
Blackpool today, aiming for 60mpg.
2020 BMW 520d MSport Touring My Daily
2017 Dacia Logan MCV 1.5DCi Laureate Wifes
1996 Land Rover Defender 90 County SW 300TDi My Toy
2003 Ford Mondeo ST220 3.0 V6 My Other Toy
2017 Dacia Logan MCV 1.5DCi Laureate Wifes
1996 Land Rover Defender 90 County SW 300TDi My Toy
2003 Ford Mondeo ST220 3.0 V6 My Other Toy