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GeorgeG



Member Since: 05 May 2011
Location: Dorset
Posts: 88

United Kingdom 
Accuracy of OBC

Now I've finally ordered a new SD4 I can start worrying (hopefully unnecessarily) about various aspects of the FL2. One feature I am interested in is members experience of the average mpg figures indicated on the car's display compared with brim to brim figures, which are clearly more accurate. Different vehicles OBC's vary a lot - my wife's last three VW's were about 10% optimistic, whereas my son's Subaru is maybe 2% pessimistic. Some cynics argue that most manufacturers build in about 10% error to provide their customers with a bit of feelgood factor.

On an extended test drive over about 60 miles I recorded 34.4 mpg. Demo cars I tried at various times generally were showing in the mid to high 20's mpg. If the OBC is as much as 10% optimistic this is a bit of a concern. However, I suppose demo vehicles tend to complete many very short journeys, usually in urban are.

Post #104246 4th Jun 2011 12:03 am
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dunroof



Member Since: 24 Nov 2010
Location: <> Yes, still being stalked by another member!
Posts: 1785

We've had this debate before. I think it reads high and is of amusement value only, but a lot of people think it's pretty accurate.

Post #104248 4th Jun 2011 4:53 am
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egipp



Member Since: 29 May 2009
Location: East Gippsland
Posts: 230

Australia 2009 Freelander 2 i6 SE Auto Santorini Black

I found the OBC, the GPS, and filling to the brim gave results to within 2% of each other so the OBC would appear to be fairly accurate over a longish trip.

Post #104250 4th Jun 2011 6:23 am
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Swingwing



Member Since: 03 May 2011
Location: None
Posts: 125

Brim to brim is the only accurate measure and I am getting about 33mpg, although my OBC seems quite accurate. BUT, with the aerodynamics of a bread van, wide tyres, 4-wheel drive (but only 95/5 split most of the time) and gearing to enable off-road capability, that's not bad. It's been said before in different posts -if fuel economy is an issue then the Freelander 2 is not for you. It's a fun machine. I went off-road 2 days ago and I was blown away with what the machine can do - enjoy. Smile

Post #104253 4th Jun 2011 8:23 am
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landy19840



Member Since: 13 Mar 2011
Location: Non
Posts: 1817

Israel 2007 Freelander 2 TD4 SE Manual Zermatt Silver

Just dont even look! You don't buy a land rover for fuel economy!

Post #104254 4th Jun 2011 9:13 am
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athelstan



Member Since: 03 Nov 2009
Location: Reality
Posts: 2657

When vehicle manufacturers test their products for average mpg/kpl they are tested under a permitted regime where all additional electrical equipment i.e. air conditioning, sat nav, lights, etc., in fact anything that requires power from the engine is switched off, and optimum tyre pressures are scientifically observed. The vehicles are also not fully loaded i.e. with passengers and cargo. This results in the lowest possible fuel consumption, and is the prime cause of why Joe Public never exactly repeats those test results in everyday motoring.

There is however help on the way because the rules for measuring a vehicle's fuel efficiency are being replaced. The original system originated in Sweden - the "urban/country/motorway" - that averaged out fuel efficiency. The new fuel consumption test is known as "NEFZ" or in english: New European Test Cycle.

This has only two criteria: Town and Country. It revolves around the time spent in either environment with a max speed limit of 120kph over a timeframe of 1200 seconds. This period is split into two segments of two thirds of the time spent in town, and the other third out of town. The road speeds attained within these time frames over a simulated average drive for each model variant form the database. The performance model is all very complicated but it is said that it will reflect more accurately the time spent driving by the majority of vehicle users. The NEFZ will apply to all new vehicles sold in the EU from 2012.

My guess is that it may be more accurate but Joe Public will still not match the manufacturers published consumption figures. Sad

Post #104255 4th Jun 2011 10:41 am
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landy19840



Member Since: 13 Mar 2011
Location: Non
Posts: 1817

Israel 2007 Freelander 2 TD4 SE Manual Zermatt Silver

Just filled up from empty and my range says 320 miles!!!

Post #104257 4th Jun 2011 12:49 pm
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Wing



Member Since: 26 May 2010
Location: Manchestor
Posts: 309

England 2013 Freelander 2 SD4 HSE Lux Auto Santorini Black

Did a comparison with OBC and pen and paper recently. OBC reported 35mpg old method 34.4

Post #104265 4th Jun 2011 2:16 pm
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Past master



Member Since: 30 Jun 2010
Location: Isle of Ely
Posts: 2710

United Kingdom 

Demo cars will always show ultra-low mpg because they are either driven for short distances with a cold engine or thrashed by people who borrow them for the day. The Freelander (especially manual) is not bad on consumption: mine is the best I've ever had apart from my first car - a minivan - BUT it will give you poor figures on a cold engine.

Post #104266 4th Jun 2011 2:19 pm
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Wing



Member Since: 26 May 2010
Location: Manchestor
Posts: 309

England 2013 Freelander 2 SD4 HSE Lux Auto Santorini Black

landy19840 wrote:
Just filled up from empty and my range says 320 miles!!!
Shocked

Mine normally reports the range on a fresh tank to be around 500 miles, which works out to be pretty true when driving in normal urban traffic, on a good run "mix of motorway 75mph, country and town driving" that can rise to almost 600 miles.

Post #104267 4th Jun 2011 2:23 pm
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Past master



Member Since: 30 Jun 2010
Location: Isle of Ely
Posts: 2710

United Kingdom 

That's my experience too - range 500-600 miles. But that's only on long journeys. I would get less if I were just using the car around London, especially with a cold engine.

Post #104270 4th Jun 2011 2:32 pm
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hutchingsp



Member Since: 08 Jan 2011
Location: UK
Posts: 90

Re: Accuracy of OBC

I've had an SD4 for a couple of months now.

The OBC consistently reads 36.4-36.5mpg, my own calculations from brimming the tank consistently come out at 34.4mpg.

Post #104276 4th Jun 2011 4:07 pm
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landy19840



Member Since: 13 Mar 2011
Location: Non
Posts: 1817

Israel 2007 Freelander 2 TD4 SE Manual Zermatt Silver

I drive as if every journey could be your last! And you all have the wrong car if you want mpg!

Post #104288 4th Jun 2011 6:10 pm
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BrianAbbott



Member Since: 28 Dec 2010
Location: Teesdale
Posts: 169

United Kingdom 2011 Freelander 2 SD4 GS Auto Ipanema Sand

I've found the consumption per OBC is about the same as a measured tankful to tankful gives me. However, the last 20-30 miles range displayed on the OBC runs down in only 10-15 miles.

A related point, the speed gauge is exactly accurate compared with GPS speed - I'm used with previous cars to the speedo being 10% or so optimistic (eg 75 displayed is really 70). Brian

MY11 FL2 SD4 GS
Extras to same spec as XS apart from the Satnav, plus Xenons.
Ipenema Sand, Ebony.

Post #104292 4th Jun 2011 6:37 pm
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dunroof



Member Since: 24 Nov 2010
Location: <> Yes, still being stalked by another member!
Posts: 1785

By law they car over read 10% above true speed, but never below. The speedo is pretty accurate, spot on or a mile or two above true speed. I still say the OBC is a inaccurate.

Post #104329 4th Jun 2011 10:56 pm
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