[AlanHo]

Hi.

How on earth do you achieve these figures? I just run mine for 5000 km and if I do my very best I get around 20 Km/l, but normally I get around 17-18 Km/l. I mostly do around 90 km/h on highway and 130 on freeway's.
But then Again I never top off the tank when I fill it, I think I will do this the NeXT time. Oh it's a 2012 1.6 CRDI

/Jakob

Your figures are very close to mine as posted above.

In your units - my last two tanks averaged 20.4 km/l and 18.7 km/l.  I don't usually drive at the high speeds you quoted though.

[Asterix]

Hi Jakob

Many new car owners have stated that the good fuel economy didn't start before doing 10.000-15000 km so there might be better consumption ahead, but the fact that you do 130 on the motorways doesn't do any good.
It will increase the consumption significantly, just compared to doing 110 km/h instead.

I get around 5,6 in my 2008 CRDi 5 speed here in the wintertime, and 5,3 in the summer, so I understand you would expect to achieve better figures.

[Phil №❶]

Excellent work Alan.  I have the 'needle'  fuel gauge (FD) I would probably get 100 km with the warning light on, but I am one who keeps his car half full, not so much damage at the bowser @ AU$1.55 for unleaded premium 95 which I use.

I am always intrigued by people who do this. You visit the servo 2x more than necessary and effectively your car has only a 30lt tank, which if true, you would probably complain about.
More time driving around with a full tank = more weight & less fuel economy. 

[AlanHo]

Excellent work Alan.  I have the 'needle'  fuel gauge (FD) I would probably get 100 km with the warning light on, but I am one who keeps his car half full, not so much damage at the bowser @ AU$1.55 for unleaded premium 95 which I use.

I am always intrigued by people who do this. You visit the servo 2x more than necessary and effectively your car has only a 30lt tank, which if true, you would probably complain about.
More time driving around with a full tank = more weight & less fuel economy. 

I brim the tank and let it run to nearly empty - then I brim it again. Thus the average fuel load over the life of a fill is half full.

To be honest I have not noticed any difference in economy between when the tank is full and when it is nearly empty. I do accept that in theory it should make a difference - but by how much I have no idea.

It would make an interesting experiment - hmmmm - something to think about

Watch this space............

[Phil №❶]

Yes it is a technical difference. The object of great fuel economy and a decent size tank is to minimise servo visits & like you, we do the same here. Unless you have a girlfriend there, I stay away from them like the plague.

[Lester]

Excellent work Alan.  I have the 'needle'  fuel gauge (FD) I would probably get 100 km with the warning light on, but I am one who keeps his car half full, not so much damage at the bowser @ AU$1.55 for unleaded premium 95 which I use.

I am always intrigued by people who do this. You visit the servo 2x more than necessary and effectively your car has only a 30lt tank, which if true, you would probably complain about.
More time driving around with a full tank = more weight & less fuel economy. 

Mmm, got me thinking, how much does 55 litres of petrol weigh?

[Doggie 1]

Twice as much as 27.5.

[rustynutz]

Me thinks it's 40 odd kgs.....

[AlanHo]

53 litres of petrol weighs 37.68 kg

53 litres of diesel weighs 45.05 kg

(Density of petrol being 0.711 kg/l. Density of diesel being 0.85 kg/l at normal temperature and pressure)

[Doggie 1]

Were you an engineer or something?   

[AlanHo]

Were you an engineer or something?   

Frayed so - mechanical and electrical qualifications. It's still in the blood.

Here is a bit more info to explain why diesel cars get better fuel economy than petrol - diesel contains more energy per litre

53 litres of Diesel contain 568 kWH of energy

53 litres of petrol contain 509 kWH of energy

[Doggie 1]

Then why does LPG with its higher octane rating give less power?

[Phil №❶]

Because the molecules of fuel are much further apart (gas vs liquid) & it's chemical formula.

[AlanHo]

Then why does LPG with its higher octane rating give less power?

53 litres of autogas (lpg) contain 382.5 kWH of energy - which is 75% that of petrol.

The octane rating of a fuel is not a measure of its energy content but a measure of how high a compression ratio it can withstand without auto-igniting (detonating). A fuel with a higher octane rating is less prone to auto-ignition and can withstand a greater rise in temperature during the compression stroke of an internal combustion engine without auto-igniting, thus allowing more power to be extracted from the Otto-Cycle.

Many high-performance engines are designed to operate with a high maximum compression, and thus demand fuels of higher octane. A common misconception is that power output or fuel efficiency can be improved by burning fuel of higher octane than that specified by the engine manufacturer. The power output of an engine depends in part on the energy density of the fuel being burnt. Fuels of different octane ratings have similar densities, but because switching to a higher octane fuel does not add more hydrocarbon content or oxygen, the engine cannot develop more power..

[rustynutz]

53 litres of petrol weighs 37.68 kg

53 litres of diesel weighs 45.05 kg

(Density of petrol being 0.711 kg/l. Density of diesel being 0.85 kg/l at normal temperature and pressure)

So I wasn't too far off with my guestimate for 55 litres...

[Dazzler]

53 litres of petrol weighs 37.68 kg

53 litres of diesel weighs 45.05 kg

(Density of petrol being 0.711 kg/l. Density of diesel being 0.85 kg/l at normal temperature and pressure)

So I wasn't too far off with my guestimate for 55 litres...

  Rusty 

[Asterix]

According to The Danish Transport Authority a rule of thumb says that for every 100 kg you add to the cars weight, you will use around 4 % more fuel.

[Dazzler]

According to The Danish Transport Authority a rule of thumb says that for every 100 kg you add to the cars weight, you will use around 4 % more fuel.

I wonder if that works the same when you tow your van (I suppose aerodynamics comes into it too)

[Asterix]

Oh yes, that's quite another case.

Normally I get around 5,3 LPH in the summer. When going to work, I allways have 3 colleagues with me in the car, so that's i30 and me +250 kg.

When towing the caravan I normally get around 9 LPH at the same speeds. Car 1800 kg + caravan 1400 kg.

The drag have HUGE impact on the consumption, but I can also confirm that just a little trailer, lower than the car, with e.g 500 kg will add extra consumption.

[Phil №❶]

To move anything requires energy, if there's more "anything" then more energy is required + all the added extras, wind, altitude etc.

[peon2t]

I get around 5,6 in my 2008 CRDi 5 speed here in the wintertime, and 5,3 in the summer, so I understand you would expect to achieve better figures.

Interesting. In the (late) summer I had between 4.6 and 5.6 with my i30 GD CRDI. But now in winter the fuel consumption went up to 7 l / 100km
So the winter has a much larger impact on the consumption of my car.

Maybe it will be better when the car is a bit older. I only have 1800 km on the clock.

[Asterix]

Well, I just filled the tank today.

The 5,6 LPH was a bit optimistic...

Over the last 730 km the LPH was 6,0 but we have had temperatures below 0ºC since last fill.

[Phil №❶]

Well, I just filled the tank today.

The 5,6 LPH was a bit optimistic...

Over the last 730 km the LPH was 6,0 but we have had temperatures below 0ºC since last fill.

Once you have below 0C temperatures, there is no moisture in the air and the air is less dense, this reduces power significantly as it is the water vapour in the air that expands when heated.

[Asterix]

Well, I just filled the tank today.

The 5,6 LPH was a bit optimistic...

Over the last 730 km the LPH was 6,0 but we have had temperatures below 0ºC since last fill.

Once you have below 0C temperatures, there is no moisture in the air and the air is less dense, this reduces power significantly as it is the water vapour in the air that expands when heated.

Yes,but that's not the only reason.

When there's frost, I must let the car idle until the windscreen is cleared for ice outside and the misting ? on the inside.
All that idle doesn't do any good for economy..

...and we use the heated seats a lot and the heated rear window...

[Phil №❶]

 

We have many places in Australia where that never happens 

[Asterix]

We have many places in Australia where that never happens 

Lucky bast....   

I really have to consider emigrate to your wonderfull country.. 

[Phil №❶]

One of our Taswegian ladies emigrated to your country and is now royalty, can't promise the same for you though. 

[Asterix]

One of our Taswegian ladies emigrated to your country and is now royalty, can't promise the same for you though. 

I would expect nothing less, of course...

Mary, she is a pretty girl. 

[Phil №❶]

There ARE more,

http://www.heavy.com/action/girls/2011/03/the-20-hottest-australian-girls/

[Asterix]

There ARE more,

http://www.heavy.com/action/girls/2011/03/the-20-hottest-australian-girls/

OK, that settles it..!  I'm moving asap.