Fuel consumption

Mvu

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Jan 7, 2015
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638
Hi guys

When looking at the fuel consumption of a vehicle which one is important? Fuel consumption urban (l/100km)? Fuel consumption extra urban (l/100km)? Fuel consumption average (l/100km)

Your input will be appreciated.
 

Aghori

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May 11, 2009
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I usually go with combined, ie. urban and freeway.
 

srothman

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Mar 30, 2010
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Combined. Will give you the best indication of what you could expect for every-day use. Then add about 20% to it.
 

Pox

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Sep 13, 2005
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Just take any figures from the manufacturers with a pinch of salt. There can be a large difference between the manufacturers claimed figures and what you will get on the road.
Much better to use something like http://www.fuelly.com/ which will give you a good indication.

Independent testing of fuel consumption figures have shown that the difference between claimed and 'real' consumotion is getting worse.
 

TehStranger

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Nov 19, 2012
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6,088
Hi guys

When looking at the fuel consumption of a vehicle which one is important? Fuel consumption urban (l/100km)? Fuel consumption extra urban (l/100km)? Fuel consumption average (l/100km)

Your input will be appreciated.

Depends what your commute will be.

Will you be driving mostly urban, highway or mixed? Choose the one that applies most to you, then add some fat because the chance of reaching manufacturer figures is low. have a look on Fuelly to see what real-world figures will be like.
 

dj_jyno

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Sep 22, 2007
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None. You will not get those figures in real life.
I beat the manufacturer's urban and combined cycle fuel economy figures on almost every trip, and get within 0.5 L/100km of the highway figure. It all depends on how you drive. That's with both my previous and current cars (carburetted petrol and common rail turbodiesel, respectively)
 

ConnaF

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Feb 16, 2015
Messages
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Why do the manufactureres claim better fuel consumption than the vehicles give under normal running conditions? (And then what qualifies as normal?)

Another stupid question is why are there less smaller diesel cars available than there were 3 years ago? Is it because of the cost on the diesel engines maintenance, expensive to maintain or because of the conspiracy that oil companies are paying the manufactureres to have them removed from their product line.

I would also say that when it comes to manufacturers specs on fuel consumption you can also add 10-15% for normal driving conditions
 

SauRoNZA

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Combined.

Then add 2l/100 to get a real world value.

Rather ignore the manufacturers claims completely and look at the stats on Fuelly.com for any car you are interested in.
 
Last edited:

SauRoNZA

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Jul 6, 2010
Messages
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Why do the manufactureres claim better fuel consumption than the vehicles give under normal running conditions? (And then what qualifies as normal?)

Another stupid question is why are there less smaller diesel cars available than there were 3 years ago? Is it because of the cost on the diesel engines maintenance, expensive to maintain or because of the conspiracy that oil companies are paying the manufactureres to have them removed from their product line.

I would also say that when it comes to manufacturers specs on fuel consumption you can also add 10-15% for normal driving conditions

Because they are tested in a lab on a rolling road with equal configurations based on regulation.

It's meant for you to compare one car to another, not really to work out the real world fuel consumption.

As for your second question petrols have just become so much better in the same 3 years that Diesels don't have the automatic advantage. Most small petrol cars are turbocharged now where they weren't a few years ago.
 

ConnaF

Active Member
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Feb 16, 2015
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Because they are tested in a lab on a rolling road with equal configurations based on regulation.

It's meant for you to compare one car to another, not really to work out the real world fuel consumption.

As for your second question petrols have just become so much better in the same 3 years that Diesels don't have the automatic advantage. Most small petrol cars are turbocharged now where they weren't a few years ago.

Make sense that they test the cars in a laboratory to keep the testing standard but then they should mention the testing conditions and test specifications.

I think it's to save manufacturing costs and the smaller car market doesn't justify a more expensive diesel engine... Check this list on fuelly.com that shows the cars according to their fuel consumption. I'm not sure how accurate it is or what the source of the info is.

http://www.fuelly.com/forums/showthread.php?t=12166
 
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