official consumption figures

[Velocemitch]

Anybody know where I can get the official consumption figures for my 170 bhp Monte Carlo?.

I'm intending to do an economy run with the Motor Club tomorrow night and we need to provide the official figures, ie not something pulled down of the internet via Autocar etc. Helpfully the owners manual just says these figures were not known at time of going to press. (that probably means Skoda hadn't programmed the cheat system at the time!).

 

On a Seat for instance it's on a label stuck inside the boot. I can't find that on mine.

[Llanigraham]

It isn't in the Handbook, but there are figures in the Sales Brochure.

[Jimrod]

If you go here you can find the official government stats for any car - http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx

[Velocemitch]

Ok thanks, I did find an old brochure which had the same figures being shown on the website. 

Pleased to report the Car returned just short of 70mpg over a 30 mile run at an average of 33mph, mixed roads, urban, country and a short stretch of Motorway (where I slip streamed a curtainsider for a few miles!).

Sadly although we got the lowest consumption we were beaten by an MR2 which clocked 60mpg!

[paulfjr]

Velocemitch your MPG figure is amazing. What gears were you at 33 mph? And I have a MR2 as well - I assume the MR2 MPG figure was higher than that above or your 70 MPG figure is incorrect, if the MR2 had a lower consumption??

[oldstan]

When, eventually, the time comes to sell the Yeti, one of the things I won't miss is the fuel consumption.

 

Round town and country (everyday mix of short and reasonable journeys) has returned a remarkably constant 32 or 33 mpg over four years.  A recent longish but easy going journey along the A303/A30/M3/M25 and a bit of round the town driving gave 37mpg.  But on the way home via M4/M5 we got 31mpg. (admittedly a reasonably quick journey time was made).

 

It shows it really doesn't like sustained motorway speeds.

[Jimrod]

When, eventually, the time comes to sell the Yeti, one of the things I won't miss is the fuel consumption.

 

Round town and country (everyday mix of short and reasonable journeys) has returned a remarkably constant 32 or 33 mpg over four years.  A recent longish but easy going journey along the A303/A30/M3/M25 and a bit of round the town driving gave 37mpg.  But on the way home via M4/M5 we got 31mpg. (admittedly a reasonably quick journey time was made).

 

It shows it really doesn't like sustained motorway speeds.

 

I found in my SEAT Exeo with the 170 diesel that even though the high speed MPG was rated well above the Yeti's due to aerodynamics I would average around 50-52 at a steady 70mph but it dropped to 42 at 80 and low 30's at 90. A lot depends on how far over the motorway speeds you go! Annoyingly the lower 143bhp model had longer gearing so was doing the same revs at 80mph as mine at 70 because of "Sports" gearing - stupid in a diesel estate!

[Llanigraham]

The Yeti has got the aerodynamics of a slightly squashed brick, so to expect good fuel consumption at max motorway speeds is futile. I find that drive over 60 and it drops quickly so I don't drive at 70. Still seem to get to places just a quickly though.

 

And thankfully I can get into the upper 40's with my diesel!

[Velocemitch]

The event was an economy run, the idea was to beat the official figures by the largest margin possible, not just get the lowest consumption. Hence why the MR2 beat us but was slightly less economic. We were also beaten by an MX5 too. The rules seem to work better if the car is a bit of a gas guzzler as it's easy to beat something by a percentage if the initial figure is lower.

 

I was astonished too with that result, I normally average about 43 to 45 in general driving, but obviously on this particular event every effort was made to save fuel, coasting downhills in gear (not neutral as that would use more fuel), turn it off if stationary for any reason, accelerate like a slow thing going slowly etc etc. Like I said we slip streamed a curtainsider at 56mph up the A1M and the instant readout was well up into the 70's and 80 mpg. (Yes I know bit naughty really)

 

it's all good fun though and makes a change from charging about trying to be the fastest everywhere..

 

I tried it a couple of years ago in a Mk1 Fabia and failed miserably when the second fill up at the end of the event went wrong and an extra Gallon went into a the reserve tank and tripled the consumption!.

[fabiamk2SE]

Why does it use more fuel in gear coasting than at tickover?

[Velocemitch]

As I understand it on tickover it's pumping fuel through to keep the motor running, but when coasting with no throttle it's not doing........... so I'm told.

[fabiamk2SE]

But the engine would cut out wouldnt it?

[Toxicvrs]

As I understand it on tickover it's pumping fuel through to keep the motor running, but when coasting with no throttle it's not doing........... so I'm told.

You've been told wrong. No different to idle

Sent from my iPad using Tapatalk

[Velocemitch]

You've been told wrong. No different to idle

Sent from my iPad using Tapatalk

Fair enough.

[bigjohn]

As I understand it on tickover it's pumping fuel through to keep the motor running, but when coasting with no throttle it's not doing........... so I'm told.

It's only when you are on the overrun  that the fuel doesn't flow through the injectors. If on tickover be it stationary or coasting (out of gear and/or clutch in) then fuel flows. IE If you are travelling down a hill with foot off the throttle you are probably on the overrun so fuel is usually turned off. You can tell as the instant consumption changes to "---- mpg" rather that something like "200 mpg" 

[bigjohn]

When, eventually, the time comes to sell the Yeti, one of the things I won't miss is the fuel consumption.

 

Round town and country (everyday mix of short and reasonable journeys) has returned a remarkably constant 32 or 33 mpg over four years.  A recent longish but easy going journey along the A303/A30/M3/M25 and a bit of round the town driving gave 37mpg.  But on the way home via M4/M5 we got 31mpg. (admittedly a reasonably quick journey time was made).

 

It shows it really doesn't like sustained motorway speeds.

 

Must be the shape of the car. I get reasonable fuel consumption figures out of my Superb 1.4tsi at UK motorway speeds -  usually over 49mpg  (drops a bit around town though!) - However my Panda 1.2 does mid 40's around town , drive it on the motorway this drops to about 38mpg   - poor for such a small car, albeit shaped like a brick!

Edited 17 November, 2015 by bigjohn

[longedge]

consumption changes to "---- mpg" rather that something like "200 mpg" 

I've often wondered (when I had nothing better to do) why they chose 200 as a cut-off. I could understand 999 but I imagine it's just arbitrary or possibly the point at which measurement fails. Should --- really be ∞ ?

[fabiamk2SE]

It's only when you are on the overrun that the fuel doesn't flow through the injectors. If on tickover be it stationary or coasting (out of gear and/or clutch in) then fuel flows. IE If you are travelling down a hill with foot off the throttle you are probably on the overrun so fuel is usually turned off. You can tell as the instant consumption changes to "---- mpg" rather that something like "200 mpg"

But theres so little fuel going in at tickover anyway, that it reads a --- if you put it in neutral and roll

And i know theres fuel going in then, or it would stall .

Edit: i found this response on another site:

"Yes, depending on the degree of "negative" flywheel torque being scheduled by the driver demand, the fuel may be competely shut off. (in fact, due to modern emissions limits and the importance of either being at exactly lambda 1 or zero fuel, modern cars are much quicker to get into DFSO (decel fuel shut off) than they used to be)

This is also compounded by the minimum usable injector pulse width. Below a certain cylinder air flow value, the fuel injection pulse width is so short (typically when <1.5ms) that the fuel delivery quantity becomes non linear, and in order to prevent lean or rich excursions, the injectors have to be turned off competely.

The only thing that might cause the injection quantity to remain above zero during a full dsfo event is catalyst over temperature (where fuelling is maintained at lambda 1 during decel to prevent the lean exotherm from over heating the cat. (but you usually have to be drivinng pretty hard to get this)

As for why the engine doesn't stall or misfire, thats because the fuel quanity control is now very very good (as it has to be for emissions control) and careful transient fuel mass management avoids partial rich or lean misfires.

(however, using DSFO isnt the most economical way of driving!) (but that's a whole new topic;-)"

It seems theres abit more to it than i thought...

Edited 18 November, 2015 by fabiamk2SE