VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy

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Wed 12 Feb 2014 11:40
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

Recently purchased new-shape Sharan with 132000 miles and full dealer service history but MPG is much lower than Mfr claimed figues:

Urban: 32mpg (mfr: 40.9)

Extra urban: 45mpg on mixed roads (mfr: 57.6mpg) (this is my real gripe)

Motorway: 44mpg (mfr: combined average: 50.4mpg).

Tyres are Michelin Energy. It switches off at traffic lights and I follow gear change indicator recommendations.

The DPF light is not on and it performs well. Anyone any thoughts on what might be causing this poor economy?

To give an indication of my driving style, I have a 2009 Passat Bluemotion 2 with the same 2.0 common-rail engine (but 110bhp with 5spd manual) and normally get 45mpg urban and between 58 and 64mpg on country and dual carriageway roads.

Thanks, Anted

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Wed 12 Feb 2014 11:52
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - unthrottled

The Sharon is a big vehicle. The numbers aren't spectacular, but not way out.

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Wed 12 Feb 2014 12:24
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

The Sharon is a big vehicle. The numbers aren't spectacular, but not way out.

Thanks, you made a good point. The Passat is as light as a feather in comparison to the Sharan!

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Wed 12 Feb 2014 12:28
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

I have read that DPF blockages can cause poor economy. Do any of you know whether a partial DPF blockage can occur that causes economy to worsen but not sufficient for dashboard DPF light to come on?

Also, is it possible to have a bluemotion engine re-mapped / chipped? My local mechanic tells me that the Bluemotion is as economical as it is going to get - but I am aware that the VW CR diesel engine comes in 110 / 140 / 170 editions and am wondering whether perhaps a re-map could help economy further?

Thanks, Anted

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Wed 12 Feb 2014 14:07
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - skidpan

Remaps/chips do not improve mpg. To put it simply a diesel car requires a certain amount of power to maintain a certain speed, the fuel to produce that power does not change even with a re-map, no clever bloke and a laptop can change that. Read the adds carefully, they all contain weasel words that mean you can never take them to court, they never promise, they simply suggest you may get better mpg.

Drive slower, you WILL get better mpg.

Also consider that even if a wonder chip did improve your mpg by 5% how many miles would you need to do to recoup your £400 outlay. Quick tap at the calculator for your Sharan suggests about 55,000 miles. Not an instant solution is it.

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Wed 12 Feb 2014 14:19
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - madf

It is WINTER

Expoect 20% more fuel used.

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Wed 12 Feb 2014 15:16
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - unthrottled

A winter with record rainfall. Everyone's economy is down a bit.

Could the handbrake/brakes be dragging slightly (probably not on an 11 plate car). Failing that, the usual suspects of boost leak or EGR malfunction (although the latter should trigger a fault). But you'd expect sluggish acceleration/black smoke with these symptoms.

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Wed 12 Feb 2014 15:19
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Collos25

We are not getting much more from a BM Up.

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Thu 13 Feb 2014 09:19
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

That puts things in to perspective!

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Thu 13 Feb 2014 09:18
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

V helpful. I'm not looking for any more power so will shelve the 'chip' idea.

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Wed 12 Feb 2014 20:26
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - craig-pd130

I'd echo the other comments. Mid-40s mpg on open roads / motorways is what I'd expect. The Sharan is a big old bus and not especially aerodynamic.

Ignore the manufacturer's EU figures, they bear no relationship to real-world driving. It's not VW's fault, its the EU that specifies the test regime.

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Wed 12 Feb 2014 21:15
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Nutkey

There is a brilliant discussion here on MPG - cumminsengines.com/uploads/docs/Secrets%20of%20Bet...f - much of it relates to trucks, but many parts are still relevant.

Also see www.dft.gov.uk/vca/fcb/the-fuel-consumption-testin...p

In particular:

1) For every 10 degree F drop in temperature, aero drag increases by 2%.

2) The manufacturer MPG test is conducted at an ambient temp of 20-30 degrees.

3) Winter diesel, as others have pointed out.

4) It's been windy. This affects things, and a tailwind will never cancel out what you lose in a headwind.

5) Manufacturer test is on a rolling road, not old tarmac.

6) Allegedly, the rules allow manufacturers to overinflate tyres, run the test at altitude (less air resistance), and seal up all the gaps. For all I know it's legal to fold the mirrors in too.

I purchased a 2.0 TDI Alhambra (aka Sharan ) with 7K miles and FDSH (i.e. none!) a few days ago. We got 42.5mpg average on a mixed drive from Cambridge to Milton Keynes and then looking for ages for a spot in the IKEA car park, and then back on a windy day (the way back was more like 49 with the wind behind us). Where possible, dead at the speed limit with cruise control. Exceeded 70 for some overtakes on the dual carriageway. Didn't thrash it around town (Milton Keynes roundabouts) but didn't hold back either.

I kept an eye on the instantaneous, and it seemed a fair bit better once properly warm (after 10 miles). If you've been getting 45mpg mixed driving, I don't think you're doing badly. I'd expect a bit better than 44 on the motorway based on what I've seen so far - but what speed are you at?

Edited by Nutkey on 12/02/2014 at 21:16

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Thu 13 Feb 2014 09:35
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

Thanks to you and others for helpful comments. The analysis above of differences in winter to summer is very interesting.

Nutkey, I am delighted that you are getting v similar MPG to me, because it indicates that despite mine having done 132k there is no specific hardware or software fault causing this. But it would be good if MPG was better for both of us! I tend to stick to speed limits (my 5 year old has learnt to read the speedometer).

The thing that puzzles me is that I am getting near to the mfr claimed MPG on my Passat but I (or should that be we?) are not on the Sharan/Alhambra, but with the same driving style.

It occurred to me that one difference is that the 2011-> Sharan/Alhambra has an auxillary heater. I knew nothing about this until my mechanic demonstrated that there is an extra, little (2cm diameter) exhaust approximately below the position of the driver's side front foglight and this little motor starts up at temperatures below 10 degrees centigrade to provide additional heat to the cabin to warm / demist it faster.

I got 24mpg this morning on a 4 mile school trip (I know, I know, we should have walked) and we all had coats on. I would have prefered the better economy to a little bit more heat, if I could de-activate the Aux heater.

1: Does anyone know if it is possible to take the fuse for the Aux heater out to see whether it improves MPG? (If it does, I might consider fitting a bespoke under-dash switch to only activate the Aux heater when I want to)...or have I got the wrong end of the stick?

2: Can anyone explain more about this mysterious little motor? Does it run from diesel or is it electric? Does it de-activate once the car enginer has warmed up, or only once the ambient outside temperature is above 10 degrees?

Thanks again for all replies. Anted

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Thu 13 Feb 2014 10:48
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Nutkey

It's only anecdotes, but www.honestjohn.co.uk/realmpg/volkswagen/passat-2005 suggests that you are not alone in getting much closer to the manufacturer figures on the passat.

My wife got 28.5mpg last night on a 2 mile urban run, cold start both ways, no traffic, followed by faffing about parking at the end (driving only sensible option, she's 30 weeks pregnant and it was late at night). She came back very thankful for the parking sensors!

Somewhat disappointed to see I can't buy a Haynes manual for the Alhambra - off to look on fleabay for a workshop manual....

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Fri 14 Feb 2014 19:33
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

This afternoon I got 37mpg on a 12 mile journey from cold (ambient 7 degrees): journey comprised 2 miles town, 10 miles 40-50mph country roads.

On the way back, I waited until the temperature gauge was on about 85 degrees and re-set the fuel computer. At steady 50mph for 6 miles, before I had to stop at a junction, MPG was 59.3 average. So that is better than the manufacturer's claimed MPG! Making adjustments for presumed over optimism of speedo and computer, its about right.

Clearly the Sharan is much dearer to run with a lot of cold starts. Presumably due to the diesel used by the Auxillary heater, and the secondary heater matrix taking heat from the engine so it warms up more slowly.

Anyone any other observations? Anted

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Thu 13 Feb 2014 11:41
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - jc2

6) Allegedly, the rules allow manufacturers to overinflate tyres, run the test at altitude (less air resistance), and seal up all the gaps. For all I know it's legal to fold the mirrors in too.

That is a load of rubbish;get yourself a copy of the regulations!

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Thu 13 Feb 2014 11:54
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Nutkey

6) Allegedly, the rules allow manufacturers to overinflate tyres, run the test at altitude (less air resistance), and seal up all the gaps. For all I know it's legal to fold the mirrors in too.

That is a load of rubbish;get yourself a copy of the regulations!

Pleased to hear it. I said allegedly. Got a link? I looked and could only find the DfT link.

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Sat 15 Feb 2014 08:55
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Collos25

The auxillary heater does not use any extra fuel except when the fan is on and the vehicle is turned off ,the fuel required is the amount to top up the battery so not very much.

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Sat 15 Feb 2014 22:44
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

Thanks for that info. Anted

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Thu 17 Apr 2014 21:27
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

Trip to Dordogne over Easter got 50.9mpg average on the way here over the whole trip, all terrain and speeds but mostly avoided toll roads/80mph. Absolutely delighted.

As for the car itself, even on 5.5hr journey between La Rochelle and Sarlat-La-Canada on all the D roads (don't ask...I didn't realise the sat-nav was set to avoid toll roads) I didn't feel tired at the end of the journey. What a great long-haul familobile. Anted

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Tue 15 Jul 2014 13:41
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Nutkey

Trip to Dordogne over Easter got 50.9mpg average on the way here over the whole trip, all terrain and speeds but mostly avoided toll roads/80mph. Absolutely delighted.

Real or from the computer? My Alhambra's trip computer over estimates MPG by 2-3mpg based on filling up to the point where the pump clicks.

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Mon 9 Feb 2015 20:50
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

Trip to Dordogne over Easter got 50.9mpg average on the way here over the whole trip, all terrain and speeds but mostly avoided toll roads/80mph. Absolutely delighted.

Real or from the computer? My Alhambra's trip computer over estimates MPG by 2-3mpg based on filling up to the point where the pump clicks.

Ah, that was from the computer only so probably a bit less in reality.

I have just bought some Vredestein M+S Quatrac 3 tyres for the front wheels to keep on all year - much better grip as I was getting wheelspin on wet roads and fuel economy seems to have improved a few MPG too on longer runs. Just need some snow now to try them out properly!

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Wed 16 Jul 2014 12:19
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - Brit_in_Germany

>The auxillary heater does not use any extra fuel except when the fan is on and the vehicle is turned off ,the fuel required is the amount to top up the battery so not very much.

That is not my understanding. Although the aux heater is like the "Standheizung" which you can use to warm the car before it is switched on, these are designed to speed up the heating of a running car when the temperatures are low, so they will be increasing fuel consumption.

For Collos, try searching "Wasserzusatzheizung" or "Zuheizer".

Edited by Brit_in_Germany on 16/07/2014 at 12:28

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Mon 9 Feb 2015 20:52
VW Sharan 2.0TDI SE Bluemotion 2011 (7N) - VW Sharan 2011 (new shape) poor fuel economy - anted

>The auxillary heater does not use any extra fuel except when the fan is on and the vehicle is turned off ,the fuel required is the amount to top up the battery so not very much.

That is not my understanding. Although the aux heater is like the "Standheizung" which you can use to warm the car before it is switched on, these are designed to speed up the heating of a running car when the temperatures are low, so they will be increasing fuel consumption.

For Collos, try searching "Wasserzusatzheizung" or "Zuheizer".

As it is an electric heater, please help me understand why it has an exhaust? The air that comes out of it is red hot.

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