Unexpected thirsty cars.
Discussion
C-J said:
Not sure what age the Aygo above is, and if new whether it is much different to the old Aygo/107/C1 3 cyl 1L?
However similar to the 107 poster above, i regularly monitor mpg on our 107 (owned from 2008) and it never does less than 55mpg, and a motorway run at 65-70ish gives 60mpg, maybe a bit more. mpg values measured over repeated brim to brim fills.
To get 30mpg or even 40mpg from ours would take some effort!
But the point was, around town, on b roads at 55mph it was amazing on fuel.
Sit at 75-80mph and it was then worse than far bigger cars I owned.
As said above, the only thing official MPG figures tell the consumer is what the car does on the official cycle. Which was what? Accelerate to 110kmph, then slow down to 45kmph and cruise for the rest of the 7km test route so you average 50kmph over the test.
It is about buying the right car for the job. I had use of a 9 speed E220d that was incredible sat at 80mph, it would be doing 65-68mpg.
However, round town from a reset it would be low 30s, it is a lot of car to keep getting going which kiils consumption.
You then see on the Merc forums, those who bought it and do lots of sub 10 mile journeys complaining that they are only getting 34mpg vs the quoted 55mpg figure, while those that sit on motorways are saying "something wrong with your car, mine never dips below 60mpg".
I will just say, we actually had a 107 on holiday, I did always wonder if the Aygo was geared a little different or if it needed more time to loosen up? I think I swapped it after 3 months or so and no more than 3000 miles.
I just found it incredibly bouncy on the main roads.
My Lotus Elise S2 111S was very economical. I can't remember the mpg now, but I think it was easily over 40, even if enjoying the performance. I later traded it in for a Lotus 2-Eleven s/c and the following week attended a trackday at Brands Hatch. I filled the car right up to max at the petrol station just down the hill from Brands, drove the one mile to the circuit, went out for the 2 or 3 slow sighting laps, then did one 15 minute session at full speed. After that, the fuel gauge was showing empty, which I assumed was a mistake, but I drove to the nearest petrol station anyway - it was indeed nearly empty.... 
Olas said:
Buy the car with the best BSFC and choose gearing to suit your intended use (city/motorway etc) if you are bothered about the distance you can cover on a full tank.
Where can I obtain the BSFC figures to compare the cars I am considering?I'm looking at a 1.0 Ecoboost Fiesta, but a used 1.0 Ecoboost Mondeo for the same money might be more comfortable to drive. What will the BSFC be on those, and which will give me best fuel consumption do you think?
my old smart brabus struggled to do 30mpg - I put this down to the remap and the fact that it had barn door aerodynamics
SLK55 - 18mpg, managed to get it up to 32mpg once on a long run by driving at 55-60 mph
The SLK 32 would do 30mpg all day (I guess smaller engine and not always having the supercharger engaged)
SLK55 - 18mpg, managed to get it up to 32mpg once on a long run by driving at 55-60 mph
The SLK 32 would do 30mpg all day (I guess smaller engine and not always having the supercharger engaged)
Olas said:
MPG is a misleading figure and it is not accurate to compare one car against another because they have different engines with different swept volumes and different torque curves.
They have different gear ratios
The have different CD and frontal area
So the comparison is meaningless..
The more accurate and transparent way to compare is to use BSFC (Brake Specific Fuel Consumption)
This is a measure of how much fuel is required to produce X power for Y time.
By removing other variables we more accurately compare engine against engine.
The biggest difference you can make to the ways car drives is to optimise the gearset, which will make the subjective measure of MPG improve markedly, although the engines mechanical efficiency will not change.
Buy the car with the best BSFC and choose gearing to suit your intended use (city/motorway etc) if you are bothered about the distance you can cover on a full tank.
I am not aware of any manufacturers offer alternative gearsets; since we all drive complete cars, real world MPG is exactly the comparison to use for fuel consumption; engine efficiency, Aerodynamics, weight, gearing, transmission efficiency, driving conditions and style all have a bearing. They have different gear ratios
The have different CD and frontal area
So the comparison is meaningless..
The more accurate and transparent way to compare is to use BSFC (Brake Specific Fuel Consumption)
This is a measure of how much fuel is required to produce X power for Y time.
By removing other variables we more accurately compare engine against engine.
The biggest difference you can make to the ways car drives is to optimise the gearset, which will make the subjective measure of MPG improve markedly, although the engines mechanical efficiency will not change.
Buy the car with the best BSFC and choose gearing to suit your intended use (city/motorway etc) if you are bothered about the distance you can cover on a full tank.
Wife's 1.6 Renault Megane auto could not match the fuel consumption of the 4.2 XF which replaced it, even around town, but the longer the journey, and higher the pace, the greater the difference
Swole said:
I always figured the old R53 Mini wouldn't be so bad. Little 1.6, ok supercharged but still pretty weak. £60 to fill, so around 50L at £1.20pl, returning 280miles to a tank of mixed driving so somewhere around 25mpg. Unnecessarily expensive to run for a commuter so sold it on the next guy.
yeah town driving not their strong point. My Mrs would get 25-28mpg round town in hers. If I took it out for a countryside blast I would get about the same. We took it from Wiltshire up to Snowdon and back at a casual cruise and it averaged about 42mpg. Could easily do 30-35mpg without trying.
gizlaroc said:
OK, maybe I was being a bit ott with the figures.
But the point was, around town, on b roads at 55mph it was amazing on fuel.
Sit at 75-80mph and it was then worse than far bigger cars I owned.
As said above, the only thing official MPG figures tell the consumer is what the car does on the official cycle. Which was what? Accelerate to 110kmph, then slow down to 45kmph and cruise for the rest of the 7km test route so you average 50kmph over the test.
It is about buying the right car for the job. I had use of a 9 speed E220d that was incredible sat at 80mph, it would be doing 65-68mpg.
However, round town from a reset it would be low 30s, it is a lot of car to keep getting going which kiils consumption.
You then see on the Merc forums, those who bought it and do lots of sub 10 mile journeys complaining that they are only getting 34mpg vs the quoted 55mpg figure, while those that sit on motorways are saying "something wrong with your car, mine never dips below 60mpg".
I will just say, we actually had a 107 on holiday, I did always wonder if the Aygo was geared a little different or if it needed more time to loosen up? I think I swapped it after 3 months or so and no more than 3000 miles.
I just found it incredibly bouncy on the main roads.
The Aygo I had was shocking. It was a 19 plate with auto box that was really annoying. Had to downshift to maintain 75mph on hills of the M40 and even then it couldn’t keep up. But the point was, around town, on b roads at 55mph it was amazing on fuel.
Sit at 75-80mph and it was then worse than far bigger cars I owned.
As said above, the only thing official MPG figures tell the consumer is what the car does on the official cycle. Which was what? Accelerate to 110kmph, then slow down to 45kmph and cruise for the rest of the 7km test route so you average 50kmph over the test.
It is about buying the right car for the job. I had use of a 9 speed E220d that was incredible sat at 80mph, it would be doing 65-68mpg.
However, round town from a reset it would be low 30s, it is a lot of car to keep getting going which kiils consumption.
You then see on the Merc forums, those who bought it and do lots of sub 10 mile journeys complaining that they are only getting 34mpg vs the quoted 55mpg figure, while those that sit on motorways are saying "something wrong with your car, mine never dips below 60mpg".
I will just say, we actually had a 107 on holiday, I did always wonder if the Aygo was geared a little different or if it needed more time to loosen up? I think I swapped it after 3 months or so and no more than 3000 miles.
I just found it incredibly bouncy on the main roads.
City car I’m sure they are good on fuel but for motorway I’m glad I only needed it for a day.
The cheap rental was offset by the extra fuel cost.
Dog Star said:
My first car was a 957cc Fiesta Pop+, X reg (ie 1981). 55bhp. Might have been 45.
Now one would think that in a light (700kg?), small car that it'd be economical.
But no! Every thing I tried to do it did 31mpg maximum - got it "tuned" (remember krypton tuning!), changed parts and filters, tried driving like a saint. 31mpg.
Strange. My first car was a 1983 Mk1 Fiesta with the same engine (only 40bhp, apparently). That averaged 38mpg over about 60,000 milesNow one would think that in a light (700kg?), small car that it'd be economical.
But no! Every thing I tried to do it did 31mpg maximum - got it "tuned" (remember krypton tuning!), changed parts and filters, tried driving like a saint. 31mpg.
Mr E said:
Sten. said:
2019 E200. It's apparently got 'mild hybrid technology' and the usual 9 speed auto, start/stop etc. Average of 27mpg with careful, mixed driving over the last year. And it's slower than a week in jail.
Again. My 10 year old thumping great E500 shows a long term average of about 24mpg. No cylinder deactivation, no attempt at eco at all.
Reading this with interest as currently looking for a car to replace my leased van as now doing potentially 25k miles p.a. I do about 50 miles of motorway and then about 20 round housing estates then 50 miles back. Total about 120ish per day. Budget between £5k and £9k and would like something getting 60mpg on motorway.
Any candidates?
Any candidates?
Aiminghigh123 said:
The Aygo I had was shocking. It was a 19 plate with auto box that was really annoying. Had to downshift to maintain 75mph on hills of the M40 and even then it couldn’t keep up.
City car I’m sure they are good on fuel but for motorway I’m glad I only needed it for a day.
The cheap rental was offset by the extra fuel cost.
City car I’m sure they are good on fuel but for motorway I’m glad I only needed it for a day.
The cheap rental was offset by the extra fuel cost.
Our 107 (2008), also auto (semi-auto/automated manual) for the missus also used to spend a lot of time on the whole length of the M40. There is just 1 hill where a down-change is required - the big slope from J6 to J5 that some trucks struggle to crawl up.
Granted, the downchange(s) required and speed at the top might depend on traffic conditions and how loaded the car is - and if you did end up being slowed by other vehicles then getting any speed back would take a while.
But equally starting the approach southbound down to J6 at a 'good 70' it was often possible to crest at about 65 in 4th (I've done this a few times hence remembering the details). Alternatively it was a good excuse to drop a cog or 2, apply a dab of noise, and clean out the injectors!
As that is the only motorway hill anywhere it has been that i can recall it struggling with, that's not bad for a city car!
Perhaps the newer Aygo's are heavier or with higher gearing? That said, if a rental car with a few miles it should have been well 'tuned' by now to use all the hp/torque available.
RB Will said:
Swole said:
I always figured the old R53 Mini wouldn't be so bad. Little 1.6, ok supercharged but still pretty weak. £60 to fill, so around 50L at £1.20pl, returning 280miles to a tank of mixed driving so somewhere around 25mpg. Unnecessarily expensive to run for a commuter so sold it on the next guy.
yeah town driving not their strong point. My Mrs would get 25-28mpg round town in hers. If I took it out for a countryside blast I would get about the same. We took it from Wiltshire up to Snowdon and back at a casual cruise and it averaged about 42mpg. Could easily do 30-35mpg without trying.
Ford Ecoboost do seem to be particularly bad for real world consumption compared to other 3 cylinder engines. Parents get around mid thirties in a B max, they're a bit miffed that friends with various Japanese cars of a similar size are getting around 50 with similar driving. I only got 38 from a hired Focus 1.0 doing mainly rural A/B road driving.
By contrast I'm currently getting nearly 50 from a Peugeot puretech with mixed driving. Has taken a bit of getting used to that for economy it very much likes low revs compared to previous NA engined cars.
By contrast I'm currently getting nearly 50 from a Peugeot puretech with mixed driving. Has taken a bit of getting used to that for economy it very much likes low revs compared to previous NA engined cars.
Triumph Man said:
2011 MINI Cooper Countryman S All4 - averaging about 30 mpg, does reasonable runs everday, would have thought it would be better than that. my BMW 530i isn't far off that, and I cane it. Of course I am a smoother driver than she is, so that might help...
Have a diesel Countryman All4, ave 50mpg. Weezywee said:
I presume this is the same engine we have in our GLA180 although I think its a 1.6L? Either way the GLA gets around 29mpg and is just awful at economy driving. Our 1.8L TT that we swapped it for used to do easy mid to late 30’s and my 2.0 Mazda 3 is currently on 50.4mpg so the Merc engine is surprisingly thirsty
Yours will be a 1.6, Merc changed the engines around 2010 when they killed off the old 1.8 supercharged 4-pot (mine was a 2004) and put a 1.6 4-pot in its place. My dad has a 2010 C180 with the 1.6 and whilst it feels slower than my old C180 (they're not exactly hot rods so the difference isn't that great) the mpg seems to be a bit more consistent, returning low 30s around town and high 30s on a run.I also have a new Merc C200 as a works car, I've got an 80 mile drive tomorrow with a mix of town and motorways so I'll make a note of the mpg figure as a comparison. No idea what size the engine is but it's a 4-pot and sounds like it has a low pressure turbo.
RichA35 said:
My A35, which I didn’t expect to be great on mpg is worse than expected. I have seen as low as 11mpg on on 3 mile round tip to the local shops, granted that’s from cold but in comfort mode. Normal around town driving is upper teens when warmed up. Overall about 28mpg largely made better by 300 miles a week at 50/60mph on the m3. Without that I expect it would be sub 20mph which I didn’t expect.
Until I got to the 'comfort mode' bit, I thought you were talking about a 60 year old Austin 
I don't think I knew of the Mercedes A35
Weezywee said:
I presume this is the same engine we have in our GLA180 although I think its a 1.6L? Either way the GLA gets around 29mpg and is just awful at economy driving. Our 1.8L TT that we swapped it for used to do easy mid to late 30’s and my 2.0 Mazda 3 is currently on 50.4mpg so the Merc engine is surprisingly thirsty
Mazda's policy of "right sizing" engines seems to really deliver the results in real world driving, whatever the billy bulls
t test cycle figures say. My 2019 MX5 will do mid 40s even with plenty of dicking about, and on a long run will return low 50s - this is a 181bhp from a 2 litre NASP engine. I had a Mazda 3 with a 2 litre petrol engine as a courtesy car that managed similar figures too.All the downsized turbocharged petrol engines I've experienced struggle to top mid 30s, and any of them with 200bhp+ seem to be really hopeless and worse than my ancient 4.2 V8 Jaguar.
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