John's Greek C5
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Re: John's Greek C5
You should be able to change that to MPG.
Poke the button on the end of the washer stalk and it should cycle through various options including MPG~dl/100km.
6.7/100km does sound excessive. It's a long time since I thought of fuel consumption in those terms but the Volvo 240s we had for work were around 4.5 - and Volvos are notoriously thirsty (I had one and can confirm), as are most SAABs but one of the lads had a SAAB - 99 I think with a V4 and that used around 3.2/100.
Poke the button on the end of the washer stalk and it should cycle through various options including MPG~dl/100km.
6.7/100km does sound excessive. It's a long time since I thought of fuel consumption in those terms but the Volvo 240s we had for work were around 4.5 - and Volvos are notoriously thirsty (I had one and can confirm), as are most SAABs but one of the lads had a SAAB - 99 I think with a V4 and that used around 3.2/100.
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Re: John's Greek C5
I should set mine to metric - that is more than I get

Will be filling up tomorrow most likely so a good opportunity.
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Re: John's Greek C5
Did he do a lot of downhill driving? That's 88mpg!!myglaren wrote: 03 Feb 2020, 20:57 the lads had a SAAB - 99 I think with a V4 and that used around 3.2/100.
Pete
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Notice the BX is still top the list but sadly gone
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Re: John's Greek C5
There is a big discrepancy between your figure and mine quoted above Chris, mine is 62/1.78, how did you get yours

I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!
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Re: John's Greek C5
Litres used per 100 kilometres.. 4.54 litres in a gallon, 100km is 62.13 miles. So if you had a reading of 4.5/100 (l/100km) that would be 60mpg.
Pete
Notice the BX is still top the list but sadly gone
Notice the BX is still top the list but sadly gone
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Re: John's Greek C5
I think you've converted yours into US Gallons, Mick.... 6.7 litres @ 4.54 litres per Imperial Gallon = 1.48 gallons, @3.75 litres / US Gallon = 1.78 gallons, as you have quoted.
I don't think the 6.7 figure is right, I can't see a 1.8 C5 doing over 40 - I would expect it to be around 25 around town, and possibly 30 if treated gently on a run. 25=11.3 l/100km / 30 = 9.4 l/100km.
My Dad used to have a 1.8 8V Xantia - he got it down to 18mpg average over a 300 mile run towing a caravan hard!!
I don't think the 6.7 figure is right, I can't see a 1.8 C5 doing over 40 - I would expect it to be around 25 around town, and possibly 30 if treated gently on a run. 25=11.3 l/100km / 30 = 9.4 l/100km.
My Dad used to have a 1.8 8V Xantia - he got it down to 18mpg average over a 300 mile run towing a caravan hard!!
Richard W
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Re: John's Greek C5
Thanks Pete. I can see where I went wrong. Instead of calculating litre to gallon conversion I used an app and selected US gallons in errormoizeau wrote: 04 Feb 2020, 09:48 Litres used per 100 kilometres.. 4.54 litres in a gallon, 100km is 62.13 miles. So if you had a reading of 4.5/100 (l/100km) that would be 60mpg.


I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!
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Re: John's Greek C5
Quite right Richard, thanks, corrected above in parallel with your postRichardW wrote: 04 Feb 2020, 10:01 I think you've converted yours into US Gallons, Mick.... 6.7 litres @ 4.54 litres per Imperial Gallon = 1.48 gallons, @3.75 litres / US Gallon = 1.78 gallons, as you have quoted.

I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!
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Re: John's Greek C5
Direct conversion table here
https://www.calculateme.com/gas-mileage ... ritish-mpg
https://www.calculateme.com/gas-mileage ... ritish-mpg
Pete
Notice the BX is still top the list but sadly gone
Notice the BX is still top the list but sadly gone
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Re: John's Greek C5
All gallons are equal, it's just some are more equal than others!! We often come across this problem with old pump data - performance curves with stated flows in 'Gallons per minute' - US or imperial??? We often have to work back through the power and efficiency curves to find out which!!
Richard W
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Re: John's Greek C5
The manufacturer's figures for this engine (Petrol 1.8 16V), so 6.7L / 100 KM is well within the Extra Urban to Combined categories.
Manual
Auto
Manual
Use | MPG | L / 100 KM |
Urban | 26.6 | 10.6 |
Extra Urban | 47.1 | 6.0 |
Combined | 36.7 | 7.7 |
Use | MPG | L / 100 KM |
Urban | 23.0 | 12.3 |
Extra Urban | 45.6 | 6.2 |
Combined | 33.6 | 8.4 |
Please Don't PM Me For Technical Help
Marc
Marc
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Re: John's Greek C5
Hi folks and thanks for all the mathmatical discussions. I'm afraid maths just isn't my thing, so I took a photo of the LCD today after a trip out. Here are the characteristics of the trip:
- Cold start-up
- Avg speed probably 60 KM/H
- Country roads
- Combo of 3rd, 4th and 5th gear
- Distance about 7.5 KM
The read-out is as in the photo showing (I think!) the average consumption. Looking at Marc's table, it looks about right, wouldn't you say? But I will certainly look at the plugs, air filter and injection areas discussed.
Cheers guys
John
- Cold start-up
- Avg speed probably 60 KM/H
- Country roads
- Combo of 3rd, 4th and 5th gear
- Distance about 7.5 KM
The read-out is as in the photo showing (I think!) the average consumption. Looking at Marc's table, it looks about right, wouldn't you say? But I will certainly look at the plugs, air filter and injection areas discussed.
Cheers guys
John
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Re: John's Greek C5
Yes that works out to 32.1mpg which is about right, so the fumes are your only fuel issue to resolve. 

I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!