Eco diesels

You know – VW Bluemotion, Volvo iDrive, etc.

Any experience of them, “real world” fuel consumption, reliability, longevity?

Honda DTec here. Real life average 64mpg.

VW Bluemotion just means the engine cuts out when you stop with your foot on the brake. Makes hardly difference to fuel consumption.

DezB – Member

VW Bluemotion just means the engine cuts out when you stop with your foot on the brake. Makes hardly difference to fuel consumption.

It’s a bit more than that, but I still don’t think it makes a big difference over the standard versions.

There’s stop-start, an alternator that adjusts load depending on whether you are braking or accelerating, low rolling resistance tyres, improved aerodynamics and longer gearing.

With the Bluemotion badge you have to be careful whether you are getting the actual Bluemotion model or just a normal model, with the Bluemotion pack added (which might just be stop-start, not sure).
My brother bought a 1.6TDi Golf and enquired about the Bluemotion model. The dealer reckoned he was better off getting a Match spec car & adding the Bluemotion pack as it worked out quite a lot cheaper. He still got a Bluemotion badge on the back of the car though I think, which could trick people into thinking they are getting the full monty….

W Bluemotion just means the engine cuts out when you stop with your foot on the brake. Makes hardly difference to fuel consumption.

No it doesn’t. I have that on mine and it’s not a Blue Motion model.

Blue motion uses smaller, down tuned down engines, lighter builds and more aerodynamic body work, smaller fuel tand and other tweaks. In reality you have a car that is ok on short journeys around time but is crap and underpowered on open roads so returns no more than a normal one.

you have a car that is ok on short journeys around time but is crap and underpowered on open roads

Well, that certainly doesn’t apply to my Passat, but I can’t be arsed to argue. 🙂

I currently have a BMW 320 ED.

Real world driving, drive it like a loon and your can push it to low 40’s. Normal driving ie commuting 50mpg. Motorway 60-65mpg at 75mph.

I’ve had 80mpg out of it driving like a granny.

Personally I would be looking at a hybrid of some sort, given what is happening with taxation on diesels.

Oh and it is nippy too!

We have a Volvo V40 D2 in the family and it returns 60+mpg. It’s got all the iDrive gubbins on it, start/stop etc.

Lovely understated car.

My Bluemotion Golf Estate 1.6diesel gives me on average around 65/66 mpg on motorway journeys.

Low-mid 60s from my Volvo V40 D4, mixed urban/a road/ motorway. I just went 800 miles between fill ups. I think that’s astonishing for a car with 190 horsepower which can also do 0-60 in just over 7 seconds.

Low-mid 60s from my Volvo V40 D4, mixed urban/a road/ motorway. I just went 800 miles between fill ups. I think that’s astonishing for a car with 190 horsepower which can also do 0-60 in just over 7 seconds.

Isn’t that their sporty diesel not the economy one?

Yep, but it still has start-stop and a little logo on the dash to tell you when you’re being a good eco driver.

I thought anything with “blue” in the name was because it squirts wee into the exhaust?

2.0 Passat estate. Returns 65mpg on A Road drops in town. Not as sporty as the golf tdi I had but I’m maturer now.

Yep, but it still has start-stop and a little logo on the dash to tell you when you’re being a good eco driver.

All of the economy with the fun to boot.

My Golf GTD is the same returns Fantastic mpg but goes like stink when needed.

Yep, but it still has start-stop and a little logo on the dash to tell you when you’re being a good eco driver

I had a V40 D4 as a hire car earlier in the year, I never noticed that feature but since I spent the whole time driving it like it was stolen the logo may have simply never lit up 😉

unknown – Member

Low-mid 60s from my Volvo V40 D4, mixed urban/a road/ motorway

Is this actual calculated values, or what the computer reckons?

The computer in my Ibiza (2 litre TDi with 140bhp) reckons I average anywhere between 62 & 65mpg per tank, but if you work it out it is more like 54-56mpg; which is obvious when you consider the 10 gallon tank allows you to do around 500 miles before bleating at you.

Just curious to understand how certain cars seem to have bags of performance & stupendous economy….I thought mine was pretty good; 0-60 in around 8 seconds & mid-50s economy – but there seem to be plenty of cars out there that are ~30% more powerful & perhaps 15% more economical, while also being larger & presumably heavier….

My dad has a blue motion golf. There is a blue motion technology option available on most golf models, but they don’t have the aero tweaks and other bits.

He drives it like an old man, but considering he was born in 1934, that is understandable. He told me what his mpg was, but I must admit I can’t remember what it was exactly, but it was huge. He likes to record miles traveled and fuel bought to work out the consumption, do pretty accurate.

The blue motion golf has a more powerful tune on the engine to compensate for the longer gears. Strange, but I read it in Car Magazine so it must be true.

It’s a bit more than that, but I still don’t think it makes a big difference over the standard versions.

There’s stop-start, an alternator that adjusts load depending on whether you are braking or accelerating, low rolling resistance tyres, improved aerodynamics and longer gearing.

Also the engine’s injection timing is altered at certain revs I think, and it overfuels less to spin up the turbo.

My sister has a 2008 Golf BM estate, and lives in the countryside at the top of a massive hill doing 5-10 mile commutes, and gets 60 ish.

but there seem to be plenty of cars out there that are ~30% more powerful & perhaps 15% more economical,

Well with a diesel larger doesn’t mean less economical. If you have a big turbo you can simply stuff more air and fuel in *when required* but not when it’s not. You can put an arbitrarily small amount of fuel in and get a small amount of power. Not the case with petrol which have to have a certain amount of fuel for the air volume otherwise it won’t ignite. Sort of.. FSI engines can improve on that, and the eco-boost style engines are small engines with a big turbo meaning you can vary the amount of air per stroke, so if it’s off-boost it’s economical.

Also cars have been getting quite a lot lighter lately. My Dad’s TFSI 1.2 Golf weighs 1150kg IIRC.

Thanks all. I’m considering a drop down in size from my Passat. Golf or Volvo D50 look nice. I’m generally a ptrol sort of bloke bu not convinced of hybrid as I don’t do a lot of urban driving (commuting).

Anybody had one long enough to discover which bits break? It sometimes appears some of these modern diesels come with built in obsolescence.

I’ve not long had my 2012 320d ED and it’s pretty frugal. I’ve been to the coast and back in it (just over 200 miles) and some general pottering about and it’s indicating high 50s mpg. I’ve not been able to work it out properly as I’ve not had it long enough to refill it.

It’s been getting the same if not better milage that my previous 1.6 TDCI focus but it’s a bigger car and significantly faster. I’m happy with it.

From your last post, if you’re used to petrol and you like it, stay with it.

Modern diesels have loads of things to go wrong DMFs DPFs and turbos dying from being coked up are the main ones. They can largely be avoided by servicing and useage but you don’t hear about so many problems with the petrols.

That said, over the last 5 years I bet there’s been a shedload more miles driven in diesels than petrols.

Won’t be long until the Government (rightly) lay the smack down on diesels imo.

@Bimbler – Agreed, I’ve just hedged my bets that it’ll only be on new cars.

Next one will more than likely be petrol, I’m just hoping it won’t need to be 5+ years.

FWIW, my V40 figures are the actual rather than indicated. The computer usually says 65-67 mpg and the actual is more like 61-63 (ish).

Good read here:

https://www.theguardian.com/environment/2016/sep/01/fuel-economy-just-two-cars-deliver-advertised-mileage-tests-show

Although the source website doesn’t seem to have the mpg figures on it yet….

http://equa.emissionsanalytics.com/equa-carbon-monoxide-index/

molgrips – Member

Well with a diesel larger doesn’t mean less economical. If you have a big turbo you can simply stuff more air and fuel in *when required* but not when it’s not. You can put an arbitrarily small amount of fuel in and get a small amount of power.

Also cars have been getting quite a lot lighter lately. My Dad’s TFSI 1.2 Golf weighs 1150kg IIRC

True, but the diesel V40 mentioned above is a 2 litre, with 190 bhp, which Parker’s reckon weighs 1450kg.

I find it interesting how quick engine technology must be moving on, given that this Volvo weighs 200kg more than my Ibiza and has 50bhp more power, but manages to be more economical (given that unknown has said above that his are actual figures, rather than calculated).

My drives are mainly fast a-road onto the A1, then A14 where things often slow-up but given the amount of miles I drive I have got pretty good at driving economically, so I don’t think it’s my driving style.

As above – I am not sure which direction to go in when it comes to replacing my car…..hopefully the gov’t will have decided by then whether diesel is the scourge or the devil or not & have updated their policies accordingly. I do wonder if they are going to be taxed to buggery soon & people will start making the switch back to petrol or petrol/electric hybrids.
We went petrol for our family bus, mainly due to miles driven & type of journey but tax is expensive on it (£180) and it’s not very economical (around 36mpg).

From your last post, if you’re used to petrol and you like it, stay with it.

Unfortunately I’m attracted by the fuel consumption of modern diesels. Well certainly compared to my petrol Passat. Maybe I should keep the old nail and by a small cheap petrol thing for when I don’t need the space (i.e. most of the time!).

I used to average 59mpg in my old 1.9to Ibiza.

Have cars really moved on that far in comparison?

Have cars really moved on that far in comparison?

Well yeah – the equivalent Ibiza will now do probably 10-20% more than that if you know what you’re doing. But you can now get a big Passat that’ll do similar.

True, but the diesel V40 mentioned above is a 2 litre, with 190 bhp, which Parker’s reckon weighs 1450kg.

Yeah but Volvos are heavy things, more so than other brands. And as has been done to death on here – manufacturers are getting better at aceing the tests, rather than delivering real world economy.

I am not sure which direction to go in when it comes to replacing my car

I would suggest petrol hybrid to anyone who doesn’t need to tow, carry large loads, and does over 5k a year or so.

not convinced of hybrid as I don’t do a lot of urban driving (commuting).

They do better than normal petrols even on the open road. Especially stuff like the Prius which has a load of other energy saving features besides being hybrid.

62mpg on a long trip in my 10 year old one, in the summer; the aforementioned 1 year old Golf of my dad is slower, smaller, and only gets 54mpg on a long run.

alpin – Member

I used to average 59mpg in my old 1.9to Ibiza.

Have cars really moved on that far in comparison?

Perhaps not. I also used to get anywhere between 56 & 61mpg in my old Ibiza 1.9TDi (130bhp version) as well.

molgrips – Member

Well yeah – the equivalent Ibiza will now do probably 10-20% more than that if you know what you’re doing. But you can now get a big Passat that’ll do similar.

No it won’t. I’ve got the equivalent. & I had the previous one. The previous was the 1.9TDI Sport with 130Bhp. The new one is a 2litre with 140bhp. I get less mpg with the new one, than with the old.
Weight and size are very similar & there’s not a great deal in it with regard to the power outputs; although the spec reckons the new one will do 60 about 1 second quicker.
I have to drive the new one a lot more thoughtfully/carefully to keep the mpg up. And this is on the same commute, as with the old car.

They do Ibiza’s with smaller engines that will probably beat the old 1.9TDi, but then you’re comparing completely different performance ranges.

molgrips – Member

Yeah but Volvos are heavy things, more so than other brands. And as has been done to death on here – manufacturers are getting better at aceing the tests, rather than delivering real world economy.

Yes, compared to other cars they may be. But, I was comparing it directly because unknown above is getting an actual 60mpg+ from his V40; not test figures, but actual values. I find it very impressive that a car that weighs 200kg more than mine with 50bhp more can be substantially more economical.

I find it very impressive that a car that weighs 200kg more than mine with 50bhp more can be substantially more economical.

Comparing two people’s figures is almost useless. You both drive differently on different roads and on different journeys. Someone living up North for example with all those long drags over the Pennines might do far worse than someone who lives in, I dunno, West London and does those endless 30mph suburban highways when they’re quiet.

a golf 1.2 is quicker than a prius (if its not the detuned version). It will probably be slightly less economical on a run due to its overall design (specifically the drag co-efficient and tyres), but it has a bigger boot and will be a nicer place to sit

a golf 1.2 is quicker than a prius (if its not the detuned version)

His is the 80bhp version, 0-60 in 11.5s, mine is something like 10.9s

but it has a bigger boot and will be a nicer place to sit

I don’t think it has a bigger boot tbh. His is nicer to sit in cos it’s 10 years younger, but the latest Prius are pretty nice. I wouldn’t choose one or the other for interior comfort. Also latest Prius are 140bhp and good for 70 ish mpg too. But then again much more expensive.

that’s true, 6k more expensive (base golf @ £14k, base prius @£20k, both on broadspeed), would take 284,000m to pay off the difference. perhaps these aren’t the most comparible cars to compare..

I used to have a BMW 320ed which averaged 57 mpg over the time I ran it. Motorway cruising would give over 60mpg. Theses are real figures calculated each fill rather than trip computer figures. The Merc A200cdi I have now returns an average of 51 mpg in similar driving but is nowhere as quick as the Merc was.
Hard to beat the 320ed for its blend of economy and speed.

1.0 petrol Focus here. It’ll show 59/61 mpg on a flat stretch of motorway, more if I want to drop under 70. That’s fully laden too. In town mpg is considerably less than that.

Average consumption is about 42mpg according to Fuelio, or 39mpg according to the car. Typical week of driving comprised of 2 x 8mile journeys through city traffic each day then a mixture of B roads and motorways at the weekend.

I couldn’t countenance the idea of buying another diesel after finding about all the particulates and potential damage to young passengers. Decent fuel economy is a bonus.

My 2.5 130bhp T5 will do ~42mpg on a run if I sit at 110kmh. My friends newer 2.0 140bhp does 38 on a run.

VW T6 140 DSG. 2 tonnes minimum, shaped like a brick,driven normally will return mid forties on the m-way and mid 30’s around town. But overall nearly 40mpg after 10k, and thats with a calculator not the trip computer.I’m happy with that considering the size of the thing.

Used to have a Mk6 golf 2.0tdi (the 140bhp one) with blue motion (not add on pack. Along a very twist stop start b-road commute it managed 45mpg average. I’m a reasonably erratic driver though.

My MK7 Golf 2.0tdi (the 150bhp one) with blue motion returned 44mpg. I think that’s more to do with the stiffer suspension, better tyres etc making me feel I could drive it a bit faster.

Both of these were official VW blue motion, niether were de-tuned, neither had any aero packs or longer gearing and the tyres were the standard non eco ones making this

Blue motion uses smaller, down tuned down engines, lighter builds and more aerodynamic body work, smaller fuel tand and other tweaks. In reality you have a car that is ok on short journeys around time but is crap and underpowered on open roads so returns no more than a normal one.

tosh.

I now have a BMW125d which is supposed to return something like 64mpg. Uttter, utter bobbins. 40mpg requires driving like a saint and a bit of fun on the way in this morning got it to under 30mpg by the trip computer.

Oh, and the bmw stop start works for about a minute before turning back on. Certainly the lights have never changed before it decides to go again so I suppose the Euro eco test requires a 30 second stop in it’s cycle.
VW may have cheated the regs, but all manufactures design cars to pass it and then not behave anything like that in normal driving.