I've just bought a Skoda Fabia 1.6 CR TDI 90bhp and am getting appalling fuel consumption. I've read various entries on here about the mpg improving, but generally the people are starting within 50's mpg (normally middle to high) and going into the 60's and even, according to one post, the 70's. My story is slightly different. I am currently getting around 48mpg and with the cold weather, this appears to be decreasing slightly towards 45-46mpg. My car has about 1400 miles on the clock and the mpg has been consistent from the start at 48mpg. I understand that during running in, the car should gradually get a better mpg, but I'm starting from a much lower beginning than others on here and something like a 35% increase would be required to get to anything like a reasonable figure.

I should add at this point that I drive almost exclusively on dual-carriageways with some roundabouts and a small section of single-carriageway. In general, I'm looking for something around the combined figure.

Compared to my old car (a Toyota Yaris 1.4 D4D), the fuel economy is appalling. The Yaris had slightly worse economy figures (combined 64mpg) and always achieved between 60-65mpg on this journey, from brand new. This is a Euro III engine from a 10 year old (at least) design. Therefore, I was looking forward to getting something around the combined figure for the Fabia. If the Fabia achieved anywhere between 60 and 65mpg, I would have accepted it. However, the 48mpg is just so low. My wife also has a Ford Galaxy 2.0 TD 140bhp (new shape Mark III), a Euro IV engine and can achieve 50mpg with ease over the journey and that's a much bigger engine and much heavier car.

I'm currently in dispute with Skoda as the figure is ludicrously low and nobody can offer me anything near a credible reason why. Additionally, unless it improves, I'll be spending another £750 a year on diesel over my old Yaris. At the moment, the purchase looks like a mistake of epic proportions. If the car had started in the 50's (preferably middle to high), I would continue and see how it pans out, buoyed by the entries on here explaining how it goes up. However, as it hasn't even left the 40's at the moment, the rise required is enourmous.

Your comments and advice would be most welcome.

P.S.

In every other respect I think the car is great, but I simply can't afford to have something drinking this much diesel, especially with prices rising all the time.

I've just bought a Skoda Fabia 1.6 CR TDI 90bhp and am getting appalling fuel consumption. I've read various entries on here about the mpg improving, but generally the people are starting within 50's mpg (normally middle to high) and going into the 60's and even, according to one post, the 70's. My story is slightly different. I am currently getting around 48mpg and with the cold weather, this appears to be decreasing slightly towards 45-46mpg. My car has about 1400 miles on the clock and the mpg has been consistent from the start at 48mpg. I understand that during running in, the car should gradually get a better mpg, but I'm starting from a much lower beginning than others on here and something like a 35% increase would be required to get to anything like a reasonable figure.

I should add at this point that I drive almost exclusively on dual-carriageways with some roundabouts and a small section of single-carriageway. In general, I'm looking for something around the combined figure.

Compared to my old car (a Toyota Yaris 1.4 D4D), the fuel economy is appalling. The Yaris had slightly worse economy figures (combined 64mpg) and always achieved between 60-65mpg on this journey, from brand new. This is a Euro III engine from a 10 year old (at least) design. Therefore, I was looking forward to getting something around the combined figure for the Fabia. If the Fabia achieved anywhere between 60 and 65mpg, I would have accepted it. However, the 48mpg is just so low. My wife also has a Ford Galaxy 2.0 TD 140bhp (new shape Mark III), a Euro IV engine and can achieve 50mpg with ease over the journey and that's a much bigger engine and much heavier car.

I'm currently in dispute with Skoda as the figure is ludicrously low and nobody can offer me anything near a credible reason why. Additionally, unless it improves, I'll be spending another £750 a year on diesel over my old Yaris. At the moment, the purchase looks like a mistake of epic proportions. If the car had started in the 50's (preferably middle to high), I would continue and see how it pans out, buoyed by the entries on here explaining how it goes up. However, as it hasn't even left the 40's at the moment, the rise required is enourmous.

Your comments and advice would be most welcome.

P.S.

In every other respect I think the car is great, but I simply can't afford to have something drinking this much diesel, especially with prices rising all the time.

are you going off the mpg readout or by calculating it over a tankful?

my unmapped vrs reads 43mpg average which is way below the 55mpg it should read. From what ive seen the computers are a bit pessimistic sometimes.

ash

as above where areyou getting the figure from

if from comp read out on dash just ignore its always wrong

p.s cold weather will mean more fuel used

If it's any consulation my MK6 Golf 1.6 TDI (105bhp) started out at about 48 mpg but slowly improved to the current 56mpg and it looks like its improving slightly with additional milaeage.The 1.6TDI engine in my experience is not as economical as the published test results indicate . Our 2010 Octavia 1.9TDI is more economical.

Edited 21 October, 201015 yr by vwcabriolet1971

are you going off the mpg readout or by calculating it over a tankful?

my unmapped vrs reads 43mpg average which is way below the 55mpg it should read. From what ive seen the computers are a bit pessimistic sometimes.

ash

Hello,

The 48mpg is fill to fill, calculated over the tankful. The computer has been pretty accurate to this, possibly slightly optimistic. However, each journey according to the computer varies between about 43mpg and 55mpg for the exact same trip. Basically, I use it predominantly to commute to and from work, so the journey is identical each day. I've tried to determine a reason for this variance, but can't come up with anything that seems to make sense/is true all the time. Cold weather seems to reduce the mpg, but this isn't entirely consistent. Whilst I don't normally hit much traffic at all, occasionally I get a little queuing. Often, these will lead to the higher mpg figures, but it just isn't consistent. The individual trip mpg seems pretty random with no rhymn or reason I can find.

The regeneration of the DPF also seems problematic. I know when it's happening as the revs refuse to go below 1000 when completely stationary, when it would normally drop to about 750-800. The journey length is about 32miles and I've had a DPF regeneration for 3 of the last 4 journeys!! Also, while regenerating, if you come to a halt in traffic, the engine seems on the verge of stalling, seems to be struggling with load and is very lumpy. However, this varies from regeneration to regeneration as well.

I've seen a lot of complaints online about the VW Polo with the same engine (often the 74bhp version rather than the 90bhp, but both have been mentioned) when the low mpg seems to be followed by DPF issues and constant breakdowns. I'm really worried about this. It seems to be going the same way as people describe in the forum entries for the Polo.

Thanks for the reply.

as above where areyou getting the figure from

if from comp read out on dash just ignore its always wrong

p.s cold weather will mean more fuel used

Hello,

The figures are calculated from a tankful, so should be spot on. Interestingly, all the mechanics I've spoken to suggest it should get better in cold weather as the air is denser and this helps. Don't know if it's true. I appreciate it will take longer to warm up, but over 32 miles for my journeys, that shouldn't be significant.

If it's any consulation my MK6 Golf 1.6 TDI (105bhp) started out at about 48 mpg but slowly improved to the current 56mpg and it looks like its improving slightly with additional milaeage.The 1.6TDI engine in my experience is not as economical as the published test results indicate . Our 2010 Octavia 1.9TDI is more economical.

Hello,

Interesting. Unfrotunately, the Golf is a much heavier car than the Fabia. Interesting about your Octavia. It all rather suggests things are going backwards rather than forwards. DPFs in particular are a nightmare by the looks of it unless you do long distances regularly. If you don't it seems you have to take the car out specially to regenerate them which rather defeats the benefits.

Hello,

The 48mpg is fill to fill, calculated over the tankful. The computer has been pretty accurate to this, possibly slightly optimistic. However, each journey according to the computer varies between about 43mpg and 55mpg for the exact same trip. Basically, I use it predominantly to commute to and from work, so the journey is identical each day. I've tried to determine a reason for this variance, but can't come up with anything that seems to make sense/is true all the time. Cold weather seems to reduce the mpg, but this isn't entirely consistent. Whilst I don't normally hit much traffic at all, occasionally I get a little queuing. Often, these will lead to the higher mpg figures, but it just isn't consistent. The individual trip mpg seems pretty random with no rhymn or reason I can find.

The regeneration of the DPF also seems problematic. I know when it's happening as the revs refuse to go below 1000 when completely stationary, when it would normally drop to about 750-800. The journey length is about 32miles and I've had a DPF regeneration for 3 of the last 4 journeys!! Also, while regenerating, if you come to a halt in traffic, the engine seems on the verge of stalling, seems to be struggling with load and is very lumpy. However, this varies from regeneration to regeneration as well.

I've seen a lot of complaints online about the VW Polo with the same engine (often the 74bhp version rather than the 90bhp, but both have been mentioned) when the low mpg seems to be followed by DPF issues and constant breakdowns. I'm really worried about this. It seems to be going the same way as people describe in the forum entries for the Polo.

Thanks for the reply.

im new to diesels so dont know about the regeneration of the dpf

i hope everything is ok for you and turns out to be something simple

ash

I had a similar problem with my old 1.4 TDI, could get nowhere near anyone else on this forum unless I drove it really gently.

Be aware that mpg is the new 0-60.

Having said that I have had a few Golfs as courtesy cars with the 1.6 TDI and they were easily above 50 mpg. Best version with the 1.6 TDI I have driven recently though was a Passat Bluemotion which was nudging 60 mpg. There may be something wrong with your car.

Why not try and get a loan of a demo from your dealer with the same engine to see if the mpg is the same on your commute?

Wind can have a considerable impact on mpg, the Fabia is not the most aerodynamic car in the world. Have you had some strong headwinds on your commute?

I had a similar problem with my old 1.4 TDI, could get nowhere near anyone else on this forum unless I drove it really gently.

Be aware that mpg is the new 0-60.

Having said that I have had a few Golfs as courtesy cars with the 1.6 TDI and they were easily above 50 mpg. Best version with the 1.6 TDI I have driven recently though was a Passat Bluemotion which was nudging 60 mpg. There may be something wrong with your car.

Why not try and get a loan of a demo from your dealer with the same engine to see if the mpg is the same on your commute?

Hello,

I've tried driving the car in all sorts of different 'styles' and it doesn't seem to make any real difference. If anything, it prefers a bit of a rev and gentle is the worst, but it all seems really random.

The garage has inspected the car and says everything is OK, but there's no such thing as a real mechanic these days in the main dealers. Unless the car indicates a problem with something and tells them what to do, they just shrug and say it's OK. They don't seem to understand that the car computer can't possibly see every possible error, especially if a sensor is returning wrong values which are still in the normal range.

Unfortunately, the dealer doesn't have another car with the same engine and apparently there is a waiting list till at least January!! I've used a data logger to produce a graph of engine functions for a 24hr period, but there's no other car to compare it to!!

Thanks for the reply.

Edited 21 October, 201015 yr by MikeHart

Wind can have a considerable impact on mpg, the Fabia is not the most aerodynamic car in the world. Have you had some strong headwinds on your commute?

Good idea, but unfortunately, not really.

Mike, Welcome to the site.

I sense your concern...but a couple of points to bear in mind. Firstly, don't panic, mpg's are scary to start with on these CR engines. Your car is way too new to be testing for the definitive mpg's. That engine is well tight and wont' even start to give you reasonable mpg's until your have 2,500-3,000 on the clock. Ultimately, it won't produce full power and best fuel economy until it's done at least 10-15,000 miles. Remember, this is a VW/Audi group engine. Don't compare it to other makes of diesel, there is little in comparison to other engines. Your Yaris is much lighter and smaller too and your new Skoda will vastly outstrip your wifes Galaxy in every respect once run in. Skoda diesels are built to very exacting standards. They take a long time to bed in, especially as the piston speed on these latest versions is reduced (reduced engine stroke) so when running in you really need to give it some juice, and not potter around on a steady throttle. It just wont' run in if you do. Secondly, many garages have been taking delivery of their WINTER DIESEL. This has the effect of LOWERING your mpg. It contains several things in it that engines don't like and the effect is roughly (depending on the engine) 4-6% more fuel used per mile covered. Everyone on this site will see their fuel consumption going down in the next few weeks. In your case this loss of mpg's will be even higher due to the tightness of your engine so I would expect your engine to be giving around 10% less mpg for any given journey travelled. Your driving style and whether you use air con will also have a considerable effect at the moment too. But driving style is still one of the biggest influences on the mpg as you probably know. DPF's don't give any problems now and on a drive of your type will be more than fine. One other point. From reports from my friends in the motor trade, the 1.6cr engines don't like supermarket fuel. This tends to leave considerable ash in the engine and lowers mpg. There has been considerable discussion about supermarket fuel on this site. Also, check your tyre pressures, they alter quite a bit this time of year and will need weekly inflation to keep them up to pressure as the ambient temp goes down. Sorry if I'm saying stuff you already know, but like to cover everything.

One other point, an ex-colleague motor technician of mine with the Fabia 90bhp CR engine complained about his mpg not being too good. Once the car had hit 5,000 miles he found he was getting 65mpg easily. I saw him just a few days ago and he now has over 12,000 miles on the car and he regularly hits 73mpg. It just gets better and better, which incidentally, is how my 1422cc TDI engine behaves.

I note the garage didn't find anything obviously wrong with your car...that's what I would expect. Just drive it and don't worry about the fuel economy. It will come good.

Good luck Mike, please keep posting.

Edited 21 October, 201015 yr by Estate Man

Sorry Estate Man but you sound like a Skoda salesman.

MPG is why a lot of people buy these diesels. VW engines (including the Tsi )are not delivering on their fuel consumption promises.No point in buying an ECO car that burns 50% more fuel for the first two years of its life.........

I'm having similar issues with my humble Fabia 2 1,2 3 cyl 70bhp. Its still struggling to return urban figures after 6000 miles in mixed driving, when my Mk1 fabia would return combined figures easily. I don't find 33mpg acceptable when I can squeeze up to 60mpg out of my 2 tonne Alhambra. The idea was to buy a small cheap to run car!!

i get on average mid to high 30's on mixed driving which defeats one of the reasons why i chose the 1.2 in the first place, i could have got a 1.9tdi for £700 extra but 1 year older

MPG is why a lot of people buy these diesels. VW engines (including the Tsi )are not delivering on their fuel consumption promises.No point in buying an ECO car that burns 50% more fuel for the first two years of its life.........

I'm having similar issues with my humble Fabia 2 1,2 3 cyl 70bhp. Its still struggling to return urban figures after 6000 miles in mixed driving, when my Mk1 fabia would return combined figures easily. I don't find 33mpg acceptable when I can squeeze up to 60mpg out of my 2 tonne Alhambra. The idea was to buy a small cheap to run car!!

Which is why diesels aren't worth it unless you do lots of miles. When I had my Mk 1 vRS, I was doing 20k+ miles per year, so 10k was up in less than 6 months. For the first couple of months it's economy was surprisingly low, before the year was out it was delivering 55mpg pretty much all the time.

I'm quite easily achieving the urban economy on my TSI, I don't expect any more than that on my short commute. 45 - 47 on a trip at the speed limits is good, I could get the 53 combined figure, but that would mean a top speed of about 50mph I reckon. 70mph will get it up to the 45-47's, but 80mph will have it down to 38. I'm very happy with the economy of my car, but remember that the brochure figures aren't promises. Some people drive around with a lead foot and expect the car to deliver the brochure economy figure - not going to happen.

From my own experience with a 3cyl 1.2, good economy was extremely hard to achieve. It's underpowered for the weight of the car, so you can spend quite a bit of time on full throttle. I did get a 50mpg average from it, but jesus, it was slow going to get it. The TSI gets better economy without having to try so hard in comparison.

Edited 22 October, 201015 yr by Mike Wrightson

Actually, one other thought.

Using the air-con will cost you up to 10% of your economy. You won't get near the book combined figure with the AC running. Lower powered engines will be worst hit by this, diesels the least hit, but every one of them will see a drop.

I keep my AC off unless it's needed.

Mike, Welcome to the site.

I sense your concern...but a couple of points to bear in mind. Firstly, don't panic, mpg's are scary to start with on these CR engines. Your car is way too new to be testing for the definitive mpg's. That engine is well tight and wont' even start to give you reasonable mpg's until your have 2,500-3,000 on the clock. Ultimately, it won't produce full power and best fuel economy until it's done at least 10-15,000 miles. Remember, this is a VW/Audi group engine. Don't compare it to other makes of diesel, there is little in comparison to other engines. Your Yaris is much lighter and smaller too and your new Skoda will vastly outstrip your wifes Galaxy in every respect once run in. Skoda diesels are built to very exacting standards. They take a long time to bed in, especially as the piston speed on these latest versions is reduced (reduced engine stroke) so when running in you really need to give it some juice, and not potter around on a steady throttle. It just wont' run in if you do. Secondly, many garages have been taking delivery of their WINTER DIESEL. This has the effect of LOWERING your mpg. It contains several things in it that engines don't like and the effect is roughly (depending on the engine) 4-6% more fuel used per mile covered. Everyone on this site will see their fuel consumption going down in the next few weeks. In your case this loss of mpg's will be even higher due to the tightness of your engine so I would expect your engine to be giving around 10% less mpg for any given journey travelled. Your driving style and whether you use air con will also have a considerable effect at the moment too. But driving style is still one of the biggest influences on the mpg as you probably know. DPF's don't give any problems now and on a drive of your type will be more than fine. One other point. From reports from my friends in the motor trade, the 1.6cr engines don't like supermarket fuel. This tends to leave considerable ash in the engine and lowers mpg. There has been considerable discussion about supermarket fuel on this site. Also, check your tyre pressures, they alter quite a bit this time of year and will need weekly inflation to keep them up to pressure as the ambient temp goes down. Sorry if I'm saying stuff you already know, but like to cover everything.

One other point, an ex-colleague motor technician of mine with the Fabia 90bhp CR engine complained about his mpg not being too good. Once the car had hit 5,000 miles he found he was getting 65mpg easily. I saw him just a few days ago and he now has over 12,000 miles on the car and he regularly hits 73mpg. It just gets better and better, which incidentally, is how my 1422cc TDI engine behaves.

I note the garage didn't find anything obviously wrong with your car...that's what I would expect. Just drive it and don't worry about the fuel economy. It will come good.

Good luck Mike, please keep posting.

Garageman, many thanks for the reply. I hear everything you're saying, but I'm still going to pursue Skoda for several reasons. Firstly, I've found out how these mpg figures are calculated from people who do it and the cars aren't even in a road legal configuration from what I can make out. They most definately aren't anywhere near the configuration and setup you or I would use. Secondly, I understand the computer learns about the other components for some time at the beginning. Initially, this involves overfueling and then leaning the engine down. This is because to do it the other way would involve the mpg declining rather than improving, which would provoke complaints.

The winter diesel issue is interesting. I can understand this happens, but my Yaris was if anything better in the winter, not worse. Don't know why, but my previous experience suggests this doesn't matter appreciably.

If you lookup VW Polo and people complaining, you'll see that people get a lot of problems with the DPF. Additionally, the people I was speaking with (who design and test for all the major manufacturers) have stated to me that DPFs are utterly pointless (apart from lowering your road tax) and cause all manner of problems. Not least that people who don't regularly do long, high speed trips end up doing special runs just to burn the DPF off. How pointless is that!! An environmental 'benefit' that actually forces you to do more miles in an uneconomical way (during a DPF run, the car is running far from optimally). Luckily, as you say, with my journeys this shouldn't be an issue.

Just to give me a point of reference, what MPG was your friend getting initially, before it went up? The people I've been referencing confirm the increase in mpg after 3,000 and then more miles, but they're telling me that 48mpg to start with is still incredibly low. It's got to get comething like another 10mpg (at least) until it gets even into the potentially reasonable band.

'Don't worry about the mpg to start with'. With diesel prices as they are and going up all the time, unfortunately, I can't do this. As far as I'm concerned, it's a fundamental dishonesty from the car manufacturers (all of them) and hearing about the configurations used to do the testing, it amounts to little more than outright lying. Using helium to inflate the tyres and massively over pressuring them (not legal) is hardly playing the game.

Many thanks for your reply.

Mike

All this talk of CR fuel comsumption, I am getting late 50-early 60 mpg from my 105 estate using Shell standard diesel. Ive had my car a month now and has 825 miles on the clock and Im happy with that.

I can understand the disappointment of Mike. I do believe the comsumption claim of Skoda is optomistic, in fact following the piece on BBC1`s Watchdog about Smart ForTwo Diesels is anything to go by, Skoda arent alone on owners disappointments.

Unfortunately, many drivers dont realise that you have to drive diesels differently to their previous petrol cars......

Regards

Grahame

Hi again Mike,

My ex-colleague who has a Fabia 90bhp Estate CR engined car initially was returning 46-48mpg. This is normal for this engine. If you drive it right and make sure it beds in correctly then the mpg just keeps going up and up. Also owners learn how best to drive this engine over time to give best mpg. The biggest mistake some drivers are making is taking high gears too early. This makes the engine work too hard and worsens fuel consumption. These 1.6cr engines need to rev a bit. Typically, these engines will gain around 8-10% more power in the first 10,000 miles if run in correctly (not pussyfooted around, and not run at constant speed on dual carriageways during the running in period) and gain much more in terms of fuel economy. Many of my friends work for Skoda and VW dealerships (I'm ex-motor tech myself), and they don't report any problems with the CR diesels. No DPF problems, except for one or two folk who don't do any miles and do only town work needing to give it the occasional blast. They work well and do a very good job. Some customers complain of low fuel consumption when compared to the EU quoted figures, but this rapidly improves. I don't quite see what your beef with manufacturers quoted fuel figures is. It's the same standard for everyone and does in fact give quite a realistic figure over and above the steady 56mph figure we used to get. It's very precise and is actually designed to give a much more realistic figure. However, at the end of the day it is only for guidance and everyone will get different figures. There are no guarantees. If your engine has only done 1400 or so miles, it hasn't even begun to bed in properly yet and it won't give it's best for some miles yet.

Unfortunately, many drivers dont realise that you have to drive diesels differently to their previous petrol cars......

Regards

Grahame

You are so right Grahame. And differently to their previous diesel too. Even bedding in the engine is crucial, and yet so many people just buy them and pootle around without giving it any real work to do, No revs, and cruising at constant speed to see how many mpg's they are getting without realising it is harming the engine in those early days. Same for petrols too of course but it's even more critical not to do it in diesels as they are very hard to bed in anyway.

Slightly of topic but with our 1.9 tdi Sport with the PD engine we were only getting 46-47 mpg when the car was new in January this year , this improved considerably once we had covered 6,000 miles and also switched to Shell standard diesel instead of Morrison diesel .

Working out the consumption from full tank to refill we are now getting 58-61 mpg driving sensibly

Slightly of topic but with our 1.9 tdi Sport with the PD engine we were only getting 46-47 mpg when the car was new in January this year , this improved considerably once we had covered 6,000 miles and also switched to Shell standard diesel instead of Morrison diesel .

Working out the consumption from full tank to refill we are now getting 58-61 mpg driving sensibly

Steven, you will probably get even more mpg's once you have passed the 10k mark...but so far you are doing brilliantly. My 1.4TDI is currently giving me an average of 53mpg mostly around town and quick fast hops down the dual carriageway for 6miles. But when I go on a proper trip she easily and I mean easily gives me 70+mpg at 70mph. Yeah, I know, it's hard to believe but it's true. My best is 74mpg, but in fourth gear at 50mph on a series of 'B' roads covering 98 miles in total.

Mike, I've just spoken to Rob, my ex-colleague about his Fabia 90bhp. He tells me this...his fuel consumption was not brilliant to start with. However, as with all engines petrol or diesel, but particularly diesel, the fuel consumption improved considerably after a couple of thousand miles. He then found by adjusting his driving style to rev the engine a bit more that it actually gave him more miles per gallon. He avoided using 5 gear too much unless above 55mph, and this gave him about 3-4mpg's more he reckons. Previously, he was taking 5th at 50mph, too early. As time went on the engine loosened more and his fuel consumption further improved and he started to see 56-58mpg much more easily. But again he found that adjusting his driving style gave another 5mpg at this stage. Now with 12,000 miles on the clock it's brilliant. His personal best is 70mpg. Don't know what sort of drive that was on.

CONCLUSION: it's a combination of a very new engine that needs to bed in, and learning the driving style best for the engine that will give you very good mpg. As a ex-tech myself, what you are experiencing is quite normal I believe. The one factor I don't know is how you drive it, but the car will be fine I'm sure. Don't worry Mike. It'll be fine.

I cant really add much to this thread other than give my own experiences.

When new my Greenline gave on average 64 mpg on long steady run. I never really tried it around town as I never use it in that way. Its basically my weekday hack to work and back (100 miles a day). Ater running in for at least 8000 miles I get about 67-70 mpg when driving normally with the odd lead foot for overtaking. This is staying at 70...ish plus a bit for speedo error..... on fast dual carriageway for the most part with some A road and a couple of towns.

His CR mpg does sound a bit low. It will definitely improve but how much is hard to say as its an entirley new engine from my older PD Greenline.

Took me ages to really get to grips with the best way to drive this diesel. I was driving it with the revs too low initially. Its happiest at 1900 to 2200. I try to keep it there be it around town or on Motorway. Definitley improves the mpg and is a smoother engine note. I actually dont even use 5th unless I am going 55-60 on level ground

As for regen. Mine does it every other day consistently around 120 mile intervals. It takes about 5-10 mins to complete. Hard to describe but it sort of drives differently and you can hear a change in the exhaust note. its not loud,just very noticeable. MPG doesnt appear to change in any way other than a slight impovement when the regen has finished. My idle RPM is unchanged when its doing this.

Its easy to say stick with it, it will improve but they really should officially state the early poor mpg if things change so dramatically. Unless they can validate that you will get a significant change after x miles then I would agree you have a valid dispute.

I wish you all the best in resolving the issue, be it self curing or a replacement car if it doesnt impove.