Fabia 1.6 CR TDI 90bhp appalling fuel consumption

[fluffmeister]

Brimming mine, so it could take no more, it just got me to Aberdeen and back (720 miles) on one tank, but I was on fumes when I got back. I wasn't in a hurry and both trips where late at night so it was cruise on set to 70mph and relax. There was no town driving at all in this though, as I was working on the outskirts of Aberdeen so straight out onto dual carriageway.

I'm usually getting around 500 ish miles to a tank in my Scout estate.

[Igloo Vindaloo]

720 miles is most imressive! My best in my Greenline II was 680 miles (74mpg) on holiday in France, fully loaded but going steady on motorways.

My average over 1 year of motoring is only 62mpg, which is worse than my previous cars, which were 'supposed' to burn 30% and 20% more fuel respectively.

Peugeot 206SW: 64mpg over 3 years, Citroen C3: 67mpg over 6 years (10% with a roofbox) - both diesels, obviously, but without the dreaded DPF.

[m collinson]

Just got back from Bickertons in Sheffield after having wipers changed under warranty and while I was there I mentioned that I was unimpressed with the fuel economy compared to my old 1.9 SDI engine. One of their top men took me out in my car to see if there was anything wrong, so, whilst we were out I asked about a few things: The widely held belief that the ECU monitors driving style, etc for 3000 miles is a load of hollihocks (or similar sounding word!!) The relatively poor fuel consumption is down to European Union regulations so basically there is sod all that we can do. I personally am looking forward to when it is out of warranty and will then consider DPF removal,etc as by then all the problems should be sorted out. Hope this has helped correct a myth or two.

Edited 16 January, 2013 by m collinson

[GeneralPurpose]

Oh dear...looks like their top man misunderstood you and/or you misunderstood him! Or...he was probably the cleaner (no disrespect to cleaners meant!). Do some proper research. I cannot speak specifically for your PD car but the newer engined CR'S, the main subject of this thread, all have programs that monitor your engine mapping etc and this takes 3k miles. It doesn't make a massive difference on diesels but does make some. The learning process is all about the engine operating parameters being set according to how the engine is used. But this is programed to happen within a certain range only and will only affect the performance of the engine in an overall minor way. It's a sort of fine tuning for engines and how you drive it in the first 3k will affect it to a very minor degree! However, on petrols it can make or break the mpg as the variables and ranges of performance are spread over a larger array of algorythms. Now the PD engines don't require a learning curve in the same way as the modern multi pump or sequential injection engines. They still learn but at a much lower level and it doesn't make an awful lot of difference in my experience. Some may interpret that as not learning, but strictly speaking that's not quite right as I understand it from our tech guys. You may find reading through the many posts in this thread useful. If you are experiencing poor mpg, there are many reasons why listed in this thread which may help you. Good luck and keep posting to let us know how you are getting on.

Edited 16 January, 2013 by Estate Man

[raisbeck]

ooh, handbags at ten paces

[GeneralPurpose]

ooh, handbags at ten paces

Crikey, I hope not. Just paid loads for my latest snappy pink twin set and matching pink handbag! I aint getting that dirty!!

[m collinson]

I was happy that this guy knew what he was talking about; he has worked for Skoda for 5 years and prior to that for Mercedes, Ferrari to name but 2. He was definitely not a cleaner, nor am I. I am sure that the problems with the CR engine stem mainly from the fact that the engine management/ emissions control et al are basically far too complicated for their own good; hence the fact that the 1.9 SDi engine is/was far more fuel efficient on account of this. Ulitmately, fuel consumption is down to driving style, etc. but this engine with it's high gearing needs to be driven a bit differently to it's predecessor. That's progress!!!

[GeneralPurpose]

Hi m, yes...without doubt he was referring to the 'dumb' PD engine. Dumb, as in my description above. Otherwise, his statement is simply not true. Although it may seem otherwise when you read this thread, there really isn't a problem for most who have the CR engines. They run sweet and give really good fuel economy. Most on here who have posted about problems had them early on in the vehicles life and didn't know how to drive them compared to their old SDI's or other types of diesels. The driving technique is different for the CR's. Most have posted to say they are now ok with the fuel economy and a few whom I followed in my survey who appeared to have big problems actually didn't have problem after they got the hang of things and the car engines had loosened up and the learning process of the ecu had finished. You can read my references to this survey in previous pages. I'm an ex-auto technician and developement engineer of 32 years experience and have had to base my finding throughout my life on the evidence I find, and I can not find anything fundamentally wrong with the CR engine or it's design. And I've looked pretty hard when involved in an engine project last year.

On another note, your PD engine is far far more efficient than the SDI engine and you should be getting more mpg's than any SDI (a good engine of course) even though you are getting expotentially more power. If you are not getting good mpg I would be looking at the many things listed earlier in this thread. It's well worth a read even though it's a long thread as many well informed individuals give good advice on this subject. There are many common things that can affect your economy, the biggest of which you mention. Don't forget the winter diesel thing either. That, and the cold weather and the devices you will use, and the longer warm up times really affect the economy. Check your tyre pressures, they go down this time of year due to temperature changes causing considerable drag. One other thing. You may want to check the engine breather pipe is clear and not blocked or partially blocked. This upsets the PD engines and their economy. It's common on the 1.9 when it's used for trips where the engine oil doesn't warm up fully every time in winter. I cleaned one out just a few days ago and the owner was surprised as he drives 8 miles to work and 8 miles to get back home. He complained of poor mpg. In winter 8 miles is not enough to get the oil anywhere near hot enough to evap the condensation and blow by products from the oil so it builds up over time and emmulsifies blocking the engine breather and sometimes the valve. There are many other things too that you can check. But the 1.9PD is economical from the experience most of us have of that engine. If you use the power all the time though, that will knock it down but you know that I'm sure. Sorry if you know some or all of this stuff but it's always worth repeating. Keep posting with anything you find.

Edited 17 January, 2013 by Estate Man

[m collinson]

Just to set things straight: I now have the 1.6 CR TDi 90 HP and it appears that it has good days and bad days re fuel on the same journeys. I am aware that this engine takes a while to get to operating temperature; oh for the old style proper fuel and temperature guages!! I did achieve 66 mpg travelling back from Chester recently so it is showing promise. BUT the old 1.9 SDi was much simpler to understand, drive, maintain and was certainly better on short runs. I am sure this thread will run and run.

[GeneralPurpose]

Hi m, sorry, I somehow put the PD engine in the frame as your car. Had a hard tiring day working from home yesterday when I replied. I would not be too concerned about your car mpg just yet especially if it's low miles. All known experience shows this engine to give good mpg's once it is run in and covered enough miles to loosen up properly. Even Mike Hart, the original poster is now getting very good miles per gallon, albeit at lower speeds at the moment. But his car is not standard and in my opinion probably needs a tweak or two. As long as you have learned to drive it the way it likes and and find the engine sweet spots, yours will be fine.There isn't anything complicated about it either, it just seems that way with all this talk about ecu's and dpf's etc. Good luck with that.

Edited 18 January, 2013 by Estate Man

[dieselV6]

Just to set things straight: I now have the 1.6 CR TDi 90 HP and it appears that it has good days and bad days re fuel on the same journeys. I am aware that this engine takes a while to get to operating temperature; oh for the old style proper fuel and temperature guages!! I did achieve 66 mpg travelling back from Chester recently so it is showing promise. BUT the old 1.9 SDi was much simpler to understand, drive, maintain and was certainly better on short runs. I am sure this thread will run and run.

Similar experience here with Roomster 1.6CR105 replacing Octavia 1.9TDI110 (200kg heavier, but lower drag). 1.6CR uses 10% more fuel in mixed town/country driving than the Octavia did over same routes. According to brochure (and the rolling road 25degC con fuel economy test), 1.6CR Roomster is supposed to use 30% less fuel than 1.9TDI Octavia. It actually uses 10% more.

Out of town and on motorway, it is possible to get closer to VAG numbers provided you drive slow enough, 50mph-55mph.

But in town and in UK weather, DPF is constantly commanding extra fuel at return stroke so that it is kept hot enough.

I really love these posts stating how after we wait for x years the mileage will improve, how we cannot drive and so on. Octavia used perhaps 5% more fuel on day 1 than it did after 3 years, and perhaps 5% more towards end of ownership at 9 years. Mk1 Superb V6TDI similarly. Both Mk1 Octavia and Mk1 Superb lived up to their brochure figures (Octy within 10%, Superb spot on).

My wife's Roomster has maxidot display clearly stating when to change gears, so I'd say it is driven as manufacturer prescribed , though I also did try higher revs as for 1.9, and fuel economy went down.

The posts stating "everyone has a good engine but you must have got a dodgy one" are equally amusing, as we have witnessed tens if not hundreds posts on Briskoda complaining about poor economy of 1.6CR and 1.4CR when compared to either 1.9TDI/PD or 2.0PD/CR.

EU fuel economy testing must change, as it stands it is a complete con, producing numbers that have little to do with real life fuel consumption in mixed use, and most cars are in mixed use. Average temperature in Europe is 9degC, not 25degC and this will truly affect the amount of fuel consumed by DPF in any town, especially at start of day from cold. For town use figures in EU testing, engine should be started cold, ambient temp kept at 9degC and either the car actually moving or airflow faithfully simulated.

Edited 18 January, 2013 by dieselV6

[GeneralPurpose]

diesel, strongly recommend you read through all the posts in this thread where all of your concerns are addressed (it's actually not too boring either), including how the EU tests are carried out. Wind and rolling resistance is factored in. On an engineering visit to a european car factory last year I've seen the tests being carried out and I can confirm that's how it happens, as does one of the articles in an earlier post in this thread on how the tests are carried out. There are only a very few people who posted here about poor mpg's that ever actually had any problems. Many have posted back here and elsewhere on the site to tell us everything is now ok.

[dieselV6]

I did read a significant portion of the thread.

25 degrees Celsius ambient temperature is what is wrong with the tests. Average yearly temperature in Europe is 9 degrees Celsius.

DPF burns considerably more fuel from cold engine start when it is colder than it does when it is warmer. Wind is only factored in as increased load due to air drag and not as increased engine/exhaust cooling. Utter nonsense method of testing.

I also recommend reading a section titled "Cycle Beating" in the Wiki entry

http://en.wikipedia.org/wiki/New_European_Driving_Cycle#Criticism

As for the mileage magically improving after 3k miles, my wife's Roomster has currently 6k+ miles on the clock. shall I wait yet another 3k miles?

End of story, my points still stand.

Edited 18 January, 2013 by dieselV6

[raisbeck]

DPF burns considerably more fuel from cold engine start when it is colder than it does when it is warmer.

Errrr...... I am not an automotive genius but what I do know is the DPF is not kept at a constant high temp by extra fuel. Its sits there as a dumb box of filtration media until it gets to a certain point of restriction, then the engine modifies fuelling for a short period to raise the temp, incinerate the soot and blow it out the back as you drive. Mine regens approx every 120 miles and doesnt appear to have any effect whatsoever on that journeys efficiency. My car wont actually regenerate until the blue light goes out. I know this because the PD is so damn obvious when it regenerates

My PD engine gives excellent economy. Whatever the problem is with the CR I dont see the DPF as a major factor, if it was my PD would be equally as inefficient as the CR engine.

I still say the lower injection pressure of the CR and the multiple injections to make it quiet and driveable have a cost.....efficiency.

Not saying I like DPF, TBH its just something else to go wrong, which it has once when the differential sensor threw a wobbler. No fault codes shown and driving unnafected but the regens went all weird . Took it to garage and they read the fault code, all sorted now with a new sensor.

[dieselV6]

DPF used to behave exactly as you described on the PDs. Then VW Group ran into quite a few angry customers after failed regens and their knee jerk reaction was to make sure DPF always burns off some soot, and occasionally burns the rest of it.

My wife's 1.6CR Roomster regeneration light comes on only every 500-600 miles, last time over a month ago, and in between the car silently burns fuel in the exhaust, there is frequently characteristic stinky smell of DPF burn after arrival. Basically, DPF takes fuel as it pleases.

I agree lower CR pressure is also a factor, though I was comparing to my earlier 1.9TDI non-PD engine. I did not expect miracles, but was quietly hoping the smaller 1.6CR will be using same or less amount of fuel as the 1.9 IP. As it stands 1.6CR uses 10% more fuel than the old 1.9 injection pump TDI did, despite 1.6CR being in a car that's over 200kg lighter.

[GeneralPurpose]

Hi diesel, your reaction is typical and understandable with respect to low mpg's. Although, there are several clues in what you say in your posts that indicate you would benefit from re-reading or fully reading through this thread. You have clearly missed some important information...for example, about the use of the gear change indicator lights and the way the car could be driven to improve mpg to name just a couple. But don't forget, this is a new generation car engine and it is markedly different in the way it has to perform. Gone are the days when not adapting to the car that you are driving fully will still result in good mpg's. It's the same for all the manufacturers with all of the newer cars. Everyone is in the same boat. Everyone is finding it harder to achieve the EU figures, IF you do not experiment with driving technique and how you use the car. I'm not trying to insult you as a driver either. But in my survey during which I examined several 1.6cr engined cars which included putting one on the dyno as the owner was so adamant it was faulty (and finding nothing wrong) the main problem was in fact the way in which they were being driven. Some owners had continued to drive their cars in the same way for the last 20 years failing to realise they needed to adapt, some of them in just a small way but after doing so, this gave them a huge improvement in fuel economy. In some instances, it was the topograhy or a combination of things, but not a problem with the engines themselves. All except one of the vehicle that took part in the survey are now returning very good mpg and many have posted back to this site with such advice. But you can read more about my findings withing this thread. Incidentally, the reason I conducted the survey was as much to help myself with my own engine project as it was to get to the bottom of the issue for others. The information I gained has been invaluable. You cannot compare the new cars with the older models you mention as they did not have to meet the stringent new standards. Many individuals here have been able to contribute considerable information about improving your mpg's. Do have a proper read. Cyle beating is of no consequence for the purposes of our discussion. It's a level playing field for all the manufacturers.

[dieselV6]

You have clearly missed some important information...for example, about the use of the gear change indicator lights and the way the car could be driven to improve mpg to name just a couple.

My wife's Roomster has maxidot display clearly stating when to change gears, so I'd say it is driven as manufacturer prescribed , though I also did try higher revs as for 1.9, and fuel economy went down.

I'd say you failed to read my post rather than I failed to read the thread.

Once again, 25 degrees Celsius ambient temperature is what is wrong with the tests. Average yearly temperature in Europe is 9 degrees Celsius.

DPF burns considerably more fuel from cold engine start when it is colder than it does when it is warmer. Wind is only factored in as increased load due to air drag and not as increased engine/exhaust cooling. Utter nonsense method of testing if your DPF software constantly adds fuel in a closed loop to keep DPF hot.

So for any car with DPF SW working as on my engine (few full regens, lots of wasted fuel to keep DPF hot at all times) in real life people who e.g start from cold in town then go on motorway will have worse mileage than people who go on motorway first, then drive in town. This might well explain the difference between the good and the bad numbers posted for mixed driving cycle.

[xreyuk]

So for any car with DPF SW working as on my engine (few full regens, lots of wasted fuel to keep DPF hot at all times) in real life people who e.g start from cold in town then go on motorway will have worse mileage than people who go on motorway first, then drive in town. This might well explain the difference between the good and the bad numbers posted for mixed driving cycle.

Unfortunately, I don't think this is correct.

I live in Southport, and every morning usually drive to Manchester or Warrington. It takes me around 30 or so minutes to reach a motorway, so I start cold in town, and then drive country roads at speeds of about 40-50mph due to traffic. So far in my Seat Leon, which is the same 1.6TDI engine here, I have averaged 65mpg over 13 or so tanks (the first couple were lower because it was low mileage). It is only recently that with the introduction of winter fuel, colder temperatures, and actually having a fault with the car which hasn't been diagnosed yet, that it's dropped.

Even with the problem, which I would suggest is either sticky brakes (2 are getting much hotter than the others), or a failing MAF (it feels so low down on power it's unreal) I'm still managing to return around 60mpg. I really don't try to drive that economically either, as I drive 70mph on all motorways, and also give it a good blast through the revs, especially up the odd hill, to keep everything clear. Low revs and a light throttle will cause carbon deposits to build up and they won't clear unless the car is driven a bit more excitedly.

With regards to revs, I was like you, following the gear changer on the car, but if you follow that the engine is at far too low revs, it really struggles to drive. I never let mine drop below 1,500RPM (except for first obviously), which means changing gear around 2,500RPM (I have longer gear ratios because it's the Ecomotive version, same as Skoda's Greenline). Since I started doing that, and doing more mileage, everything started climbing. At first it didn't, but as I learned the car I got better.

I believe if I dropped my motorway speed to around 60mph, I'd see in increase up to the high 60s for mpg. Now I know the car is rated for 74mpg combined, but that's not running at motorway speeds, that's running at extra-urban speeds, of which the average is lower.

[dieselV6]

Will you swap cars with me so that I can start saving on fuel while you pick up the bill for Roomster's thirst? Plus, again, the very line I quoted from my first post states that I did try to drive it like the 1.9 (meaning higher rpms, not really going below 1600rpm) as well as per maxidot instruction, and the results were even worse than with maxidot's "strangle the engine" policy.

What keeps pointing to DPF being the fuel waster is the fact that the car smells of DPF burn very frequently, while indicated regens (light on the dashboard) are quite infrequent given town/country cycle. I checked error codes, nothing there.

[xreyuk]

Will you swap cars with me so that I can start saving on fuel while you pick up the bill for Roomster's thirst? Plus, again, the very line I quoted from my first post states that I did try to drive it like the 1.9 (meaning higher rpms, not really going below 1600rpm) as well as per maxidot instruction, and the results were even worse than with maxidot's "strangle the engine" policy.

Plus again you seem to have not read my post. If you're not going to read other people's posts, they'll stop trying to help you.

I said that I started to drive at higher revs, at first the fuel economy didn't increase, but after a while where I learned the optimum gear changes were, it started climbing.

[dieselV6]

I do not need any help with the fuel thirsty 1.6CR as it is beyond help.

But it would be nice for a change if people stopped praising a dodgy and very variable quality engine and stop bashing unfortunate buyers of fuel wasters. All just because they were lucky enough to get a working one. Have you noticed that there are far fewer posts on 2.0CR fuel economy problems than there are for 1.6CR?

Keep in mind I bought 3 Skodas privately, with my own money, as opposed to them being given to me as company car etc. I got very good value for money from earlier cars. As I see it, if the Roomster was as close to published fuel economy figures as Mk1 Octavia 1.9 and Mk1 Superb 2.5 were, I'd save £4k on fuel over 10 years.

So in my mind, I paid Roomster's VAT free price, supposedly a good deal, and then it turns out I have to slap an extra £4k more than planned on fuel, resulting in end price of 6% above list price. Not a good bargain, would've bought Mk2 Octy 2.0CR on VAT free offer instead. Or a Yeti if I could be bothered to wait for that long.

Edited 19 January, 2013 by dieselV6

[GeneralPurpose]

I'd say you failed to read my post rather than I failed to read the thread.

Once again, 25 degrees Celsius ambient temperature is what is wrong with the tests. Average yearly temperature in Europe is 9 degrees Celsius.

DPF burns considerably more fuel from cold engine start when it is colder than it does when it is warmer. Wind is only factored in as increased load due to air drag and not as increased engine/exhaust cooling. Utter nonsense method of testing if your DPF software constantly adds fuel in a closed loop to keep DPF hot.

So for any car with DPF SW working as on my engine (few full regens, lots of wasted fuel to keep DPF hot at all times) in real life people who e.g start from cold in town then go on motorway will have worse mileage than people who go on motorway first, then drive in town. This might well explain the difference between the good and the bad numbers posted for mixed driving cycle.

Hi dieselV6, respectfully no...it's because I read your previous posts that I replied saying you needed to read further on with the posts in this thread. Helping you is all that anyone here is interested in and it's important to get that message across. Please excuse my matter of fact terminology, it's not intended to sound critical of you. I've had a lifetime of examining engines and writing reports, that's just how I am. But let me be a bit clearer if that will help. Initially, when this engine came out quite a few people were infuriated with their new 1.6cr fuel economy. This has been found to be mostly due to driving technique, and that is a fact, often not believed by some. And it is not something confined to the VAG 1.6cr engine either. It's across the board affecting Ford, Peugeot, Nissan etc etc. All get more complaints about their modern diesel engines not quite living up to expectations regarding fuel economy. I have not examined any other engines aside for the VAG 1.6cr so cannot speak for the other makes as to the cause. It's likely it's just the same for them too though. I do not and have never worked for Skoda or VAG.

Your comments about the DPF and DPF SW may be indicative that your vehicle is either not being driven correctly, or it's being used inappropriately for trips that are too slow, or too short. It could also be a fault with your vehicle which I very much doubt. Ambient temperature during vehicle testing is irrelevant for the purposes of our postings. Think about it! You also do not understand the correct way a DPF works, but that's pretty irrelevant as these are not really an issue ever if the car is driven and used correctly.

Everyone accepts you are a competent driver, but you clearly haven't yet read the posts about some of the most important factors causing poor or reduced fuel economy with this 1.6cr engine. In your previous posts you intermate that the vehicle is being driven correctly following the dash economy lights. Sadly, if you do that, your fuel economy will not be very good. I know the book tells you to do it that way but for nearly everyone, it doesn't work. It loads the engine way too much under most conditions even encouraging some of the respondents in my survey to engage 5th gear at 40mph, which is much too slow (this speed will vary of course depending on engine load, throttle setting etc). In fact in tests I have carried out on this engine (Golf 1.6cr on the dyno) we found it best to let the engine get over 2k revs at least before engaging the next gear and even higher than that in the upper gears. The engine fuel consumption rises (fuel used) considerably for any given mile driven under 18k rpm even with just the driver in the car. So the lights can give a false impression of when to change gear. Other outside factors also affect the revs when you may need to change gear to improve consumption such as wind, load, hills etc. But you know that. This is well established and all but one of the 13 drivers in my survey were following the instructions to change gear according to the dash lights and after advising them to ignore the lights and take the revs up more before changing gear, and in some cases avoid using 5th gear altogether on their 'A' and 'B' road journeys to work, their fuel economy improved expotentially. I even went out with 4 of the surveyed drivers to view their driving to help ascertain what was happening. It was always too few revs and being guided by the lights that caused the problem for them. That's actual fact. I would add that my tests, although unscientific in study, produced credible results allowing these conclusions to be reached.

My conclusion of this: Your Roomster is bigger and heavier than a Fabia and will use more fuel. Skoda and VAG group could give better advice about driving modern diesels, also better running in instructions. This modern CR engined diesel uses a much shorter stroke engine than prevously used in any VAG car. This reduces piston speed and gives a cleaner fuel burn, reducing emmissions, lengthening engine life etc etc. The trade off is that it may take slightly longer to run in and loosen up if not run in correctly, and it cannot be driven economically in quite the same way as earlier diesels with a longer stroke engine and lower gearing, especially during the running in period as there is more engine friction inertia to overcome at that time than in a longer stroke engines (pumping losses are greater). This appears to result in more fuel used to start with. Couple that with the fact drivers are not adapting to the newer type of engine with higher gearing and they get poor fuel economy. The better technique for driving this engine is to keep revs a bit higher than in previous longer stroke diesel engines and use the gears more avoiding high gears at lower speeds. The outcome is much better power and fuel economy, fewer DPF regenerations. This applies not just to when the car is running in.

Sorry if this sound a bit too contrite. This is just what I've found and is based upon the facts as I have discovered them. But as I say...these finding are not absolute and it may not always be the same for everyone. Topograhy is another biggy when considering fuel economy, and I did find one car with a faulty ecu which after being replaced made the fuel economy much more acceptable. But faults are the exception and not the rule. Also, worth noting we have the 1422cc PD 3 cyl diesel and a 1.6cr in the family. My lil sis has the 1.6 and had exactly the same problems as you until we did the driving adaption thingy. she now rarely uses 5th gear on Suffolks A & B roads and gets over 60mpg all the time. Prior to that she had the excellent 1.9PD Octavia.

PS. Would also advise listening to what xreyuk has to say. He has good experience with this engine and also had initial problems that he solved by adapting his driving technique after doing considerable research. He is full of good advice.

Edited due to being rubbish at speilling!!

Edited 20 January, 2013 by Estate Man

[seboni121]

Estate man once again your posts are bang on , I've got the cr and you right don't change gear when the dash tells you too, it makes you change up too early and labouring the engine, you need too stay in the sweet spot and this is where the turbo comes into life, needs to be around the 1700rpm approx

[dieselV6]

Once again, tried higher revs around town, 1600-1900rpm rather than the 1200-1500 that MaxiDot wants as I also though MaxiDot was insane having driven 1.9TDI (IP) for 10 years before (1.9 has most vibration in the RPM range where MaxiDot indicates), and the higher rpm increased fuel consumption, not much, about 5% but still.

Secondly, I am not comparing Roomster to Fabia, I am comparing 1.6CR Roomster to Mk1 1.9TDI Octavia, a car good 200kg heavier than the Roomster. Yet Roomster uses 10% more fuel around town.

If I can afford 2 cars in the house I can also afford a bit more fuel, it's not really that serious issue.

What really annoys me is that had I known how fuel thirsty 1.6CR is, I'd have bought 2.0CR Octavia on VAT free that was running then, not the Roomster. And I still would have saved some money over the life of the car. So it is down to brochure economy numbers, the test should be more realistic, and even if Maxidot does not show optimum gearshift points, it should show gear change points that will result close to maximum fuel economy.

As it stands, manufacturers publish figures that while comparable in theory, have nothing to do with actual fuel consumption in real life. European test is one of the worst for this. If at some point someone "invents" a DPF filter that floods exhaust with fuel below 15deg C resulting in flames out the exhaust, its effect on fuel economy in European test will be exactly nil. That says enough about how bad EU testing mode is.

Edited 20 January, 2013 by dieselV6

[Grantson]

As far as I can tell from the manual my 1.6CR is not equipped with the DPF

Ive watched my fuel economy on the drive to work drop from low 60s to low/mid 40s

coming back to this thread has reminded me to ignore the shift light although if any of the vcds experts out there know if there's a way to turn it off that would be handy

The car is due its 10k service in the next 500 or so miles Im hoping that this will help revive the economy

I've also started using fuely and I am noting which brand of fuel and which garage each tank came from