yostumpy said:

Resurrecting an old thread, interested about the under 2l/100km bit, How do you know this. I find that if I pop it out of eco, on a known downward slope, floor it for about 2/3 seconds ( up to about 75+) then knock it out of gear, whilst tapping it back into eco,it does roll an increadably long way,

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You can test the display by climbing to the top of the biggest hill you have, getting up to speed and resetting the MPG read out. At any speed above 30mph in 5th, the ECU will be in DFCO and not using any fuel. Touch the throttle at the bottom and the numbers will shoot up immediately. Conversely you could go to a race track where the MFD is maxed out at about half throttle, as soon as you slow down the readout drops from it's 25l/100km limit. I recorded around 23l/100km (12mpg) on track, but there's no way it was that good. You can also use OBD to give you relative numbers and you'll see the OBD average dropping far quicker than the MFD because 'zero' is a much more powerful number than '2' when your average is around 4. Currently sitting on an estimated 65mpg tank

In my experience the MFD will be ever more optimistic below 50mpg, and ever more pessimistic as you go above 50mph, it can be as much as 10mpg either way, although with a big enough hill the error could be massive.

The 500 is one of the worst coasting vehicles I have, light weight and worse-than-a-van aerodynamics means it coasts worse than a van. I suspect your Yaris brakes might be rubbing, as the two should coast pretty much the same. UFI coasts slightly better than a 1994 Suzuki Swift.

I have a hill I drive most days and use the lamp posts at the top and bottom to get a speed delta. UFI looses about 4km/h at the bottom, the Prius gains 4km/h

UFI said:

The 500 is one of the worst coasting vehicles I have, light weight and worse-than-a-van aerodynamics means it coasts worse than a van.

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That is completely the opposite to my experience of a few different cars, a couple of vans, and even a minibus or two.

Our 500TA is almost problematic on downward inclines whereas ALL the other vehicles I've driven (and drive) are not.

By "problematical" I mean that coasting requires constant dabbing of the brakes to keep under the speed limit.

For instance, there's a long gentle hill near here where the it's National Speed Limit at the top, then a 40mph, then 500yds(?) later down to a 30mph.

By lifting off the throttle just as you start to descend, you hit the 40mph at 40 and still with your foot off, you're smack on 30mph as you hit the 30 sign.

The 500TA is very different. If you're doing 50 or 60 at the top and lift off like the other vehicles, you have to brake for the 40, and continually brake to make it down to 30.

No other vehicle I've ever owned or driven is like this. We've lived here over 30years so I'm very familiar with the road.

Regards,
Mick.

Mick F said:

That is completely the opposite to my experience of a few different cars, a couple of vans, and even a minibus or two.

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You're talking about 'gliding' (in gear) while I'm talking about 'coasting' (in neutral). Coasting in neutral is a measure of a car's sectional density (CdA x weight). I think that's what the original question was about, admittedly I don't always use the correct term.

Gliding in gear the TA has very little engine braking, to the point that coasting in neutral is almost pointless.

yes I was referring to ''coasting'' in neutral, and it does seem to be rather good at it. I think this is aided by the 'non eco' turbo'd 85bhp, giving a short sharp burst, getting me further down the road.
However UFI , as you are a fellow 'believer' and frequent that heathen website known as 'ecomodder' I will, in this instance, bow to your greate experience with this car, and try gliding in 5th, for a while.

UFI said:

You're talking about 'gliding' (in gear) while I'm talking about 'coasting' (in neutral). Coasting in neutral is a measure of a car's sectional density (CdA x weight). I think that's what the original question was about, admittedly I don't always use the correct term.

Gliding in gear the TA has very little engine braking, to the point that coasting in neutral is almost pointless.

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Ok.
I understand. Sounds like an experiment with our 500TA vs our Clio. Clio is much heavier, so may win due to weight alone.

Maybe leave a particular spot on a gentle hill at a (say) 20mph and see what speed I get to a particular point further on. Maybe take a stopwatch too. Both tests to be in neutral.

BTW, I'm not convinced about the legality of "coasting" in neutral. I know it frowned upon at least.

Cheers,
Mick.

ah! but there is more to coasting than...er...coasting, Again I think the power and light weight of the TA win here, as ...well..

if you ever notice birds in flight, imagine a sparrow taking off, all fluff and flap and energy spent.
then notice a pigeon on a chimney pot, it launches, 5-6 almighty flap upwards then it glides in to the trees on yonder field.
So when cresting a hill or at the top of an incline, a (short almighty shove) can do wonders for the distance travelled.

Even aircraft adopt this principle now, they take off full throttle up to x thousand feet, level off, then almost glide to destination, rather than take off at 3/4 throttle and take ages, to get to altitude. The former is obviously more cost effective.

so with the light weight and the extra power, a hard short push of the loud pedal can propel the little jellymould into orbit.

yostumpy said:

yes I was referring to ''coasting'' in neutral, and it does seem to be rather good at it. I think this is aided by the 'non eco' turbo'd 85bhp, giving a short sharp burst, getting me further down the road.
However UFI , as you are a fellow 'believer' and frequent that heathen website known as 'ecomodder' I will, in this instance, bow to your greate experience with this car, and try gliding in 5th, for a while.

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I've tried coasting and gliding on the highway (at the same average speed - repeating the same loop) and steady state cruising won the day. Unfortunately the small capacity turbo uses a lot of extra fuel to keep temperatures down when on boost.

PS A TA is the only car I know of capable of making the EM top ten without even beating it's official figures.

I wonder if Fiat are guilty just like VW?
Perhaps they're ALL doing it?
http://www.bbc.co.uk/news/world-us-canada-34298259

I'm at 65mpg on this tank (with passenger 99% of the time ~8600km on the odo), so they can't be cheating too much.

Mick F said:

I wonder if Fiat are guilty just like VW?
Perhaps they're ALL doing it?
http://www.bbc.co.uk/news/world-us-canada-34298259

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The article is about the cheating the emissions standards, not about cheating with fuel economy figures, but it's an open secret that car manufacturers explore the boundaries of the legislation during official emissions tests. Some are more creative in exploring the boundaries than others. In that respect car manufacturers are not different than athletes.

VW has a serious problem. They have to recall all of these cars and fix them. However, permanently enabling the "compliant mode" might result in poor driveability that no customer accepts. I don't envy the owners of the cars involved. Will they still like their car after it has been fixed?

so the ''compliant mode'' on a TA? would that be the 'ECO' button , that enables free road tax. Does the TA comply with the low emission limit when not in ECO?

UFI said:

I'm at 65mpg on this tank (with passenger 99% of the time ~8600km on the odo), so they can't be cheating too much.

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65mpg? dash readout or fuelly?

yostumpy said:

65mpg? dash readout or fuelly?

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more important is;

average indicated AIR temp,
and average Journey (trip) speed

both are where typical UK motoring loses out,

Charlie

yostumpy said:

so the ''compliant mode'' on a TA? would that be the 'ECO' button , that enables free road tax. Does the TA comply with the low emission limit when not in ECO?

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No car manufacturer will be that stupid to make a button on the dashboard that disables compliance. If you want instant trouble with the authorities, then you should do that. "Defeat devices" aren't supposed to be detected, since they are illegal. VW hided theirs somewhere in the car's software. Nevertheless it was discovered by the California Air Resources Board (CARB) and researchers from West Virginia University. Everything FIAT's ECO mode does, can be done in normal mode by more carefully pressing the accelerator pedal.

AGH1965 said:

No car manufacturer will be that stupid to make a button on the dashboard that disables compliance. If you want instant trouble with the authorities, then you should do that. Everything FIAT's ECO mode does, can be done in normal mode by more carefully pressing the accelerator pedal.

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the Stop / Start system is a vital part of modern vehicle " low emissions" strategy,

BUT I'm not aware of any system that "KILLS" the engine when S/S becomes "unavailable"

most even have a dash mounted switch to disable it..,

I don't have an issue with ANY of this..

it's great that vehicles are becoming MORE fuel efficient..,
but it's down to drivers to actually get the most from this..,
NOT going "Flat-out" in such small engined, heavy ( safe) vehicles..,

Charlie

varesecrazy said:

the Stop / Start system is a vital part of modern vehicle " low emissions" strategy,

BUT I'm not aware of any system that "KILLS" the engine when S/S becomes "unavailable"

most even have a dash mounted switch to disable it..,

I don't have an issue with ANY of this..

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Sharp!

I'm pretty sure that car manufacturers convinced the authorities that this S/S switch is there for safety reasons only. What if your car has starting problems and you wouldn't be able to switch S/S off? That would be a serious safety issue, for example if you stop your car accidentally on a railway crossing...

To get a consistent gauge of MPG, reset your MPG AVG with every fill-up.

When I bought my 2012 Fiat 500 Sport, I saw that the MPG increased at intervals based on the miles on the engine. My MPG increased every 2,500 miles until the engine reached 10,000, and then it leveled out to be consistent. The best MPG that I ever got was in October of 2013 when I was returning from my yearly hunting trip back home and I got 52 MPG. My engine now has 77k on it, but I still get good MPG. I have three places that I get gas: Costco, Shell, and a gas station near me that dispenses non-ethanol. With Costco 89 OCT, my MPG drops like a rock in the city and HWY 28 / 35. With Costco 93 OCT, it's a bit better but not much. With Shell V-Power 93 OCT, my city MPG reaches as high as 38 but HWY it goes up to 42 MPG. With non-ethanol, it gets up to 42 HWY. Also when I used V-Power or non-ethanol, my Fiat experiences much better engine boost when taking off from a dead stop and passing. :slayer:

yostumpy said:

65mpg? dash readout or fuelly?

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Real life, the dash display is all but useless. I still gained 2mpg on this tank that I'll put down to break in. The Pop wheels/ tyres gave me 4mpg near as I can tell. My first tank was 36mpg I wonder where the break in gains will stop?

varesecrazy said:

more important is;

average indicated AIR temp,
and average Journey (trip) speed

both are where typical UK motoring loses out,

Charlie

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Temps around 20*C, mostly blasting around twisty roads in the hills.

Average speed for the last tank was around 60km/h, so still a bit short of the theoretical ideal average speed of 70km/h. Average speed doesn't really matter, you just need appropriate strategies to deal with it. Weight doesn't really matter you just need appropriate strategies to deal with it. Traffic doesn't really matter, you just need appropriate strategies to deal with it. Even at 20km/h in peak hour traffic and a 600kg load (which also ruins the Cd from 0.33 to 0.45), I'll still beat the City figure in my 1.6 Renault by at least 10%, it all just means I won't beat it by 100% like I could in ideal conditions.

thanks,
point i was trying to make is during my old commute ( reason for buying a TA punto..)

over 1st 7,500 miles gave dash indicated;
49.8 MPG, 31MPH Average speed,

15 mins at 55 / 70 MPH ( dependant on traffic / mood),
25 mins to cover last 3 miles ( Oxford - UK Traffic)

findings found;

outward run @55 MPH gave 45MPG = 12'C

return run @55MPH gave 65MPG = 25'C

unfortunately 70% of my UK driving will be at temps below 15'C,

a fair proportion will be sub 8'C..

Welcome to "Real World" Driving

Charlie

varesecrazy said:

outward run @55 MPH gave 45MPG = 12'C

return run @55MPH gave 65MPG = 25'C

unfortunately 70% of my UK driving will be at temps below 15'C,

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We have plenty of cold days here and I don't think (it's only a 20*C day today) the temp difference can account for all of that discrepancy. There's likely elevation change and prevailing winds to consider. We get quite a few 2-3* mornings, but I've never seen that sort of hit.

Bare in mind it's dangerous to draw too many conclusions from the MFD as it can be out by 10mpg in either direction.