This is the problem with big, heavy modern cars. The amount of energy required to move 1500-odd kg off from rest cripples fuel economy in town.
Even our diesel Scenic which would do 45-50 mpg out of town, would struggle to do 35 if used exclusively in urban driving. When I had to push it the other week when the clutch failed, the reason became clear!
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This is the problem with big heavy modern cars. The amount of energy required to move 1500-odd kg off from rest cripples fuel economy in town.
But you'd think the official figures would reflect that - there does seem to be a big difference in the OP's case.
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I was looking in an old ford brochure the other day and I was surprised to learn that a top spec 1992/3 Ford Granada Scorpio 2.9 V6 24V weighs 1425 KGs. My current diesel Astra weighs 1430 KGs and is wider.
An Astra heavier than a Ford Scorpio, wider, and has a longer wheelbase than a Sierra.
Vauxhall state unladen weight with a 68KG driver, full fluids and 90% full fuel tank. This (I think) might be in compliance with some E.U regulation for vehicle weights. Unfortunately I dont know what the weight measurement criteria for Fords in 92/93 was as it doesnt say.
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I get the same MPG from a V8 4.6 Ford Mustang around town
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I get the same MPG from a V8 4.6 Ford Mustang around town
I dont think so you, must be pushing it.
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19 MPG US equates to 22.8 UK. I am too old to push it
Edited by Pica on 12/03/2009 at 14:23
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When they measure the official figures using a rolling road, presumably they dial in the rollers' resistance based on the weight of the vehicle?
www.vcacarfueldata.org.uk/information/consumption....p
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Yes they do;the vehicle's weight is simulated either by flywheels and/or electrically;also the road load is fed in.The road load will be the force required to move the vehicle at a steady speed and that will be controlled electrically or by water brake;the flywheels(mechanical and/or electrically simulated)look after the inertia which is what affects acceleration/deceleration.
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Is this 'town use' all short jouneys ?
Although modern cars do warm up quickly, their fuel consumption while warming up can be very poor.
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Around town... so the engine is cold and running with a enriched mixture..
No surprise in winter...
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Around town... so the engine is cold and running with a enriched mixture..
From website (link above) official test consists of 4 back-to-back cycles of just over 3 minutes each, from cold. Ok ambient temp is 20-30, but even so, shouldn't this be fairly representative of what you're descrbing?
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The above web-site is somewhat simplistic-the emission test is done from a cold start-the fuel test is done from a hot start but this is not made clear on the web-site.I do know about this-I used to be responsible for the testing.
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the fuel test is done from a hot start
I guess that would make a difference then if a lot of OP's journeys are short. Anyone got rough figures for differences in mpg between 'cold' and 'hot' enginres?
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Hot and cold engine differences? I would estimate 25%... (Engine and gearbox oil and bearings grease will be cold so rolling resistance much higher as well)
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As far as I understand it, as a cat can be destroyed by a backfire, modern engines tend to run very rich when warming up, so tend to be very thirsty is used on cold / short runs.
This combined with the huge weight of newer cars probably makes them less efficient around town than cars 20+ years ago
MVP
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"This combined with the huge weight of newer cars probably makes them less efficient around town than cars 20+ years ago"
Cars today have a much better power to weight ratio and for a direct weight comparison I don't thing a modern car weighs anything like a 50,s Austin westminster or the like.The reason for the bad MPG is either mechanical or driver.
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But a 1986 Escort Estate 1.3L weighed 890kg - IIRC that's about the same as our mk1 1.0 Yaris.
EDIT: www.carfolio.com/specifications/models/car/?car=24...4
Edited by Focus {P} on 12/03/2009 at 12:48
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Hot and cold engine differences? I would estimate 25%
Then that would go some way to explaining the difference between OP's 23 and official urban 31.7, assuming official test doesn't attempt to compensate for it.
Seems odd that urban test doesn't specify cold start. Perhaps if they're doing the emissions from cold then they don't want to hang around while the engine cools down before doing the mpg.
And also I know it's officially only supposed to be a way of comparing between vehicles rather than an absolute 'this is what your vehicle will do' figure.
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I am a bit upset that I have bought a Zafira 1.6. Official its gets upto 49mpg. I am averaging 26 and no more than 32mpg even on a run...
I had expected to get high thirties and would have been happy with that. Considering last car was low fities its costing a fortune
I had thought that mpg figures were real life driving..Not on a rolling road
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Bazza
Age, mileage? Short runs/long?
Your post is so lacking in information as to be of little use.
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Used to have a similar grumble with a very comparable car ? a 2005 Seat Toledo 1.6 petrol. Same sort of size as a C-MAX, same size engine.
It would only give 25-28mpg around town, but I could improve that to nearer 40 by being incredibly gentle on the throttle in traffic, letting the car move in 3rd or 4th without any throttle at all wherever possible.
After a while this got on my nerves as I was creeping about everywhere, all the time. Verging on the dreaded ?mimse?. But driven with any amount of throttle, consumption was awful, so I got rid of the car, despite the fact that I generally quite liked it.
It used to give me between 250-300 miles per tank when driven with any throttle, I am now watching my 2.0 petrol Mazda 6 auto with great interest, as in theory it should be thirstier than the 1.6 Toledo. However, my first tank almost stretched to 400 miles before I needed to fill up, and that was mostly town driving on short runs (sub-8 miles) and not being particularly gentle on the throttle.
Seems to me 1.6 litre petrol engines are just not up to the job of the modern small family car. Won?t be making that mistake again.
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However my first tank almost stretched to 400 miles before I needed to fill up
Sorry, have to ask - bigger tank?
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Good point of course. I'll check it out. However, the cost to fill the Seat from empty was over 50 quid (sold it early 2008 before the fuel price spike), and it's just about the same in the Mazda.
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Yep, Mazda's tank is bigger by 9 litres it seems. Even so, it seems to me that the Mazda's economy is roughly the same as or better than the Toledo, and I don't have to drive it like Miss Daisy to achieve it. So I have a more powerful car without it costing more in fuel, and without feeling I need to mimse about the place. Which I like.
My assumption would have been that most given 1.6s are more economical than any given 2.0, but it seems not.
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Its a 58 Plate with 2100 miles on now. I am aware it may get better when run in..
The 32mpg was a run to test mpg. Brimmed it and ran on 90 percent dual carriageways at 60mph for 80 miles. Took it back and brimmed it again
For the normal driving its mostly 5-10 miles trips on 70 percent A roads. Dont have a heavy foot by any means....
In my opinion its due to the fact that its geared wrong and revves like mad at 60mph..
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The 32mpg was a run to test mpg. Brimmed it and ran on 90 percent dual carriageways at 60mph for 80 miles. Took it back and brimmed it again
Agreed, that does sound low - my mk1 2.0 Focus estate does sub-30 around town, but can be coaxed over 40 on motorway journeys. Hopefully as you say the Zafira just needs running in.
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The so called official figures cannot be for real life driving unless all drivers drive in exactly the same way.
Over the years weight has gone up. A car which weighs 1500Kgs will take 50% more energy for an given amount of accleration than a car which weighs 1000 Kgs. The same for brakeing. 50% more energy to to dissipate for any given reduction in speed which translates into more wear on the brakes.
Over the years cars have become much bigger. More frontal area means more drag. increase the frontal area by 50% and you increase the amount of power and hence fuel required to overcome the aerodynamic resisance at any given speed, assumeing the same drag coefficient for both cars.
Showing my age now, back in the mid 70s it was said that a good Carrera RS weighed about the same as a standard Mini.
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In the past,one of the motor magazines carried out a series of fuel comsumption tests on four models of cars that were available with different sized engines.They were tested in heavy traffic,town traffic,mixture of town and dual carriageway and ,lastly, motorway.The larger engtines were more economical on all vehicles and in all conditions except heavy traffic.
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I wonder if it is an idea to have somewhere on this site a section where people can post their fuel figures listing car details, type of driving and use along with the official figures as it would be a valuable resource for people who want real life figures that they may actually get.
My dads Astra 1.6 auto does 28 mpg round town and 36 on a run and that is old, well past its best and rarely does more than a 5 mile journey.
If it makes you feel any better my mums V6 Hyundai struggles to better 17 mpg round town and an average of 26 in mixed driving.
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SWMBO has a 51 1.6 auto Focus.
I did a 400 mile round trip in one day Oxford-Liverpool-Oxford, going out with three and luggage, coming back empty. Indicated 70-75 on the M40, M42 and M6, no hold-ups. Filled it full to brim on leaving and returning, and it gave 37.3. It's on about 60k.
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Overall my 1.6 (115bhp) cmax zetec improved from 35mpg to 37mpg following 36k service with new spark plugs. Wouldn't expect more than mid twenties driven cold around town, then again I've had mid forties on a cross country run. All in all same as my previous 1.6 Scenic.
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I had a 2001 1.6Zetec engined Fiesta.
Around town I could easily - without trying - average sub30mpg - and if I accelerated hard about 25mpg. Long runs ? 35-40mpg.
I got fed up. My Yaris diesel averages 55mpg around town - however I drive it (aircon on all the time)...
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If one could generalise, fuel consumption has never been Ford's strongest point.
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