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On the basis of the official Combined fuel consumption figure, I was expecting the overall average fuel consumption of my 2013 1.6 litre Focus (official Combined 47.9 mpg) to be significantly better than that of my previous 2003 2 litre Focus (official Combined 32.5 mpg). After four months the overall average of my 2013 car for a similar journey pattern is almost identical to that of my 2003 car. I'm not disappointed, just surprised. However, it does make me wonder what value the official fuel consumption figures have. I'm sure that for some people it's the first thing they look at when choosing a new car.
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There are 2 things here. One is the cars are set up to get the best numbers in the test, rather than for best economy in everyday conditions.
The other is all the tricks involved in getting the best test figures that weren't around in 2003 (stop start, low resistance tyres etc..)
We have 2 Alfas, one is a 2004 156 GTA. Its official consumption figure is 23 mpg. I regularly get 29-31 mpg (so 30% better than claimed)
The second Alfa is a 2012 Giulietta (2.0 multijet diesel 170), the official consumption figure for that is 60mpg. We regularly get around 50mpg out of that (17% less than claimed)
Also for my commute to work, I have tried economy runs in both. In the GTA I can get 36mpg, in the Giulietta I can get 55.4mpg
Progress?
Last edited by: PR on Sat 27 Jul 13 at 09:43
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It just means that the manufacturers development effort has only gone into achieving better results form the 'Official Test'. Remember that it this result that gets you a lower Car Tax charge.
I have witnessed something very similar from comparative consumption figures form the 90bhp PSA 1.6 HDi engine 2006 vs 2013.
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Its ironic that the combined test cycle, designed to cut CO2 emissions is actually increasing them!
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I bought a new Isuzu pickup a few years back - 165hp, 3.0 diesel, auto, common rail, 16v etc. So not exactly cutting edge, but reasonably modern. On a really long steady run, ie, Sweden to England, it would do 29mpg. Running around it would do maybe 27, and towing a heavy trailer (ca. 3 tons) it would do very low 20's.
My '93 Landcruiser, 165hp, 4.2 straight 6, 12V, auto, and definitely old tech (engine and transmission), will do 26 on a run, and just over 20 if towing heavy. So considering it's nearly 15 years older, more than 1/2 ton heavier, and not as aerodynamic, it doesn't use much more than the newer vehicle, and the same when towing. The only difference is the amount of smoke emitted.
So smoke aside, I'm not really sure there's been much advancement in 15 years. It would be nice to drop the old straight 6 into the new pickup though.
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I wa thinking just the reverse only recently, albeit mostly based on my experience with diesels. I 2003 I had an E270 CDi which averaged low 30s to the gallon, whereas the more powerful E250 CDI averages mid 40s. Both are autos, though the newer car has just 4 cylinders compared to the older cars 5. I've also been using a borrowed 520d for the last couple of week - it's a manual and is averaging around 50mpg. The last manual 2 (ish) litre diesel i had was an A4, and that did mid 40s. I'm sure all of them are way off the 'official' figures though!
On the petrol front even our Up! is averaging low 50s from its 1 litre petrol engine, which is certainly more than I remember my Fiat UNO achieving 20 yeas ago! If you want poor fuel economy though, you should try a '94 Audi 2.6 Cabriolet with a 4 speed auto. It's doing around 23mpg, which is almost exactly the same as our old E30 325i touring. An E90 330i averaged almost 30mpg over the 6k miles I had it, so certainly progress there
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L'es
The number of posts on here about the "Mark 3 Focus" you bought. If you don't get on with it, chop it in for something else. You could have hired one to see how you would get on, then made a decision. From your almost constant posts about this and that ,since you got it, it appears you are not that happy with it.
All new models have differing characteristics from their previous kin and I thought you were old and wise enough to do some homework, instead of comparing with Focuses you've had before.
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>> L'es
>>
>> The number of posts on here about the "Mark 3 Focus" you bought. If you
>> don't get on with it, chop it in for something else.
I love it. I was just curious as to why it doesn't give a better fuel consumption than my 2003 Focus, given the big difference in the official figures.
Anyway, you obviously need someone to be sarcastic about so it might just as well be me. It's water off a snail's back.
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And all the other threads about it? Came across as being a bit doubtful.
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>> And all the other threads about it? Came across as being a bit doubtful.
>>
You obviously need someone to be sarcastic about so it might just as well be me. It's water off a snail's back
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You've put me off buying one. I'm happy with my 1.8 Zetec S Mk2 face-lifted version at the moment. No complaints.
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Engines are now designed and mapped to do well in the official tests. What you get in the real world bears no resemblance at all.
About all the figures do is give you a basis for comparison. My 320d is supposed to do 68.9 mpg combined. I have never managed to get within 6 mpg of this over a tankful, and that was consciously driving gently in near perfect traffic (school holidays). What is rather more impressive is that I can drive it hard, and still see a genuine 50 mpg over a tankful, and I have never seen less than 46, even with extensive town work, and lots of hard acceleration.
Last edited by: DP on Sat 27 Jul 13 at 16:49
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My Mitsubishi 1.6 is not modern by any standards (2002) but I'm very happy with its economy. The official figures are 38mpg combined and 48mpg extra urban. I get a solid 42-43mpg week in week out with 30-40mph daily 10 mile runs - no urban. Its showing just over 45mpg today but its had an easy life over the last week. Just fitted some Nexen Blue eco tyres today, lets see!
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The difference in lorry fuel consumptions is a similar story, in 1984 i could get as good consumption out of my big old Cummins (not a computer to be seen) as i can out of the all singing dancing more computers than you can shake a stick at electronic things i 'steer' now, and make far better progress than the strangled modern junk.
At the end of the day if you want to propel a car of a certain weight and shape at a certain speed whilst accelerating at a given rate then the only way to achieve that is by the burning a certain amount of fuel.
I doubt many of us here actually believe anything anyone trying to sell anything says, from politics to cars to whiter than white nukem blinding washing powder.
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My Volvo is miles away from the official 62mpg. I have tried and there is no way you could get close to it - my average over the last 10K is 45.
By comparison the C5 had the same engine in and booked at 54 mpg but used to regularly return 52.
Les - I guess you need to look at the difference in power output. Technology is giving you more bhp for the same amount of fuel.
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30 years ago the average diesel engine would give out a blanket cloud of particulates: the cost of lower emissions is worse fuel consumption.
And more electronics= bigger alternators= bigger power loss when charging.
You'd all complain if there was no AC in the past 3 weeks.
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>> 30 years ago the average diesel engine would give out a blanket cloud of particulates:
Don't have to go back 30 years, just follow a Mondeo pre DPF when the driver floors it, i've seen clumps of soot coming out the exhaust of those contraptions and spattering on the road.
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>>
>> Don't have to go back 30 years, just follow a Mondeo pre DPF when the
>> driver floors it, i've seen clumps of soot coming out the exhaust of those contraptions
>> and spattering on the road.
>>
Ah, that brings back happy memories!
Finally getting my old Mondy diesel past a shed tugger I'd been stuck behind for miles on a windy single carriageway and giving him a face full of thick black smoke as I overtook in second with my foot on the floor.
Disgraceful that I gloried in it of course, but one is only human...
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>> Disgraceful that I gloried in it of course, but one is only human...
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No thats fine RR, drivers of Volvo lorries could at one time get rid of tailgaiters and punish wrongdoers by pressing the exhaust brake and throttle simultaneously and smoke the blighters out big time...so i'm told..;)
Oh and deliberately semi stalling MAN lorries when they were tough proper motors would i am informed..;) cause the cold start to kick in.
Last edited by: gordonbennet on Sat 27 Jul 13 at 20:17
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1994 Pajero. 2800cc turbo. I know cos it says so on the stickers. Built like a brick shi...outhouse (1.8 tons) Aircon works and was used all last week. I love it, but....... 17.5 mpg.
Sorry got to go, one of the Labs has just Horse and Carted under the table and it stinks. See you later.....
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>> 1994 Pajero. 2800cc turbo. I know cos it says so on the stickers. Built like
>> a brick shi...outhouse (1.8 tons) Aircon works and was used all last week. I love
>> it, but....... 17.5 mpg.
Surely there is something faulty? That's petrol territory, even if it is a heavy old beast.
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>> Don't have to go back 30 years, just follow a Mondeo pre DPF when the driver floors it
I had a Mondeo pre DPF but it was a Euro IV tuned engine (not quite as efficient as the Euro III version).... no cloud of smoke. Apart from when the EGR valve went faulty.
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>> >> Don't have to go back 30 years, just follow a Mondeo pre DPF when
>> the driver floors it
>>
>> I had a Mondeo pre DPF but it was a Euro IV tuned engine (not
>> quite as efficient as the Euro III version).... no cloud of smoke. Apart from when
>> the EGR valve went faulty.
>>
Are Euro III supposed to smoke ? The only time mine smokes is when there is a fault e.g. blown intercooler, clogged EGR, blocked boost control valve, otherwise should be smoke free. Maybe FSH isn't worth advert it's printed in.
Back to OPs comparison, he's comparing apples and bananas. 145 PS vs 182 PS and no mention of vehicle weight hatchback vs estate ? Whatabout torque figures ? No way was a ten year old normally aspirated getting close to a new turbo.
PS I'm looking forward to my RFL based on emissions refund as my car is now showing an average 53 mpg but the RFL is calculated on 44.8 mpg.
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>>At the end of the day if you want to propel a car of a certain weight and shape at a certain speed whilst accelerating at a given rate then the only way to achieve that is by the burning a certain amount of fuel.
While it's absolutely true that in order to propel a car of a certain weight and shape at a certain speed and a certain acceleration takes a unique amount of power at the wheels, the relationship between that, and the rate of fuel being burnt is affected by all of the various efficiencies along the path between the fuel tank and the wheel:
volumetric efficiency,
mechanical efficiency of the engine,
parasitic losses (alternator, water pump, oil pump, etc),
combustion efficiency,
friction lost in various seals in the drivetrain,
viscous losses in the oils used in the transmission,
friction losses in the gears,
friction losses in the bearings,
friction losses in any shaft couplings (UJ and CV joints)
and the rolling resistance of the tyres
I'm sure there a more loss mechanisms, but, it's late, and ale has been taken!
Any effort to reduce any of these loss mecahnisms can improve fuel efficiency, and as an added bonus will also tend to increase performance.
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And,of course,the requirement to run at stoichmetric(to make catalysts work) has reduced manufacturers' ability to take advantage of lean-burn to really improve fuel economy.I notice how much easier it is to move my new car by hand than ones I have owned in the past-a great improvement in rolling resistance.The fuel consumption on a number of petrol cars I have owned has not varied by more than a couple of MpG.
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>>And,of course,the requirement to run at stoichmetric(to make catalysts work) has reduced manufacturers' ability to take advantage of lean-burn to really improve fuel economy
Mazda appear to have followed another path with their latest petrol engines by being able, somehow, to run with a compression ratio of 14:1, with their 2.0 non-turbo petrol managing over 45mpg in real world driving in their Mondeo sized '6'.
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Does this mean the internal combustion engine has come full circle and we'll soon be back to 32 litre V12s producing 90 bhp ?
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>> the requirement to run at stoichmetric(to make catalysts work) has reduced manufacturers' ability to take advantage of lean-burn to really improve fuel economy
The catalyst is an example of Heath Robinson imposed by government legislation and probably doing more harm than good.
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>> The catalyst is an example of Heath Robinson imposed by government legislation and probably doing more harm than good.
While catalysts no doubt cause a slight increase in fuel consumption due to them slightly strangling the exhaust, I bet all the tech required to make them run properly actually increases engine life by preventing chronic overfuelling washing oil off the bores.
Particulate filters on the other hand.....
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>> the tech required to make them run properly actually increases engine life by preventing chronic overfuelling washing oil off the bores.
As with carburetted cars in the bad old days, all out of tune and most badly driven?
Certainly, and that makes them frugal on fuel too. But not as frugal as lean burn. That was what I meant.
I imagine lean-burn exhaust is too hot for catalysers and would melt them.
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Nothing to do with exhaust temperature!For a three-way catalyst(CO,HC,NoX) to work efficiently,the A/F(air/fuel) ratio must be at stoichmetric-about 14.5/14.7 to 1 and lean burn can be upto 20/1.Current legislation is built round catalyst technology.
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Ford Focus III - Fuel consumption of modern engines - PR
