Our Cars : Thirsty Astra

I like the Vauxhall Astra Sports Tourer. It’s an honest car, that’s well-made, well-designed and which performs well on the UK’s motorway network. And over the months, I’ve really grown to appreciate some of those clever little touches that make life so much easier. But I really wish it was more economical.

In average driving, I’m getting between 47-49mpg out of the Astra, which isn’t bad for a hack that spends much of its time on the motorway, but it’s not as good as I’d hoped for. Of course, we know that car manufacturers are working hard to produce vehicles that score well in emissions and fuel consumption tests, but can this sometimes be at the expense of real world mpg – and should we even be using the official figures as a guide at all?

It’s clear that I’m not alone in struggling to crack 50mpg in daily driving. The figures suggest an average of 48.5mpg, which is 77 per cent of the claimed combined figure. When reader Michael Sum got in touch about his Sports Tourer, his findings echoed mine completely. ‘I’ve had the 1.7CDTI Ecoflex for three months and it’s covered just short of 6000 miles, averaging 50mpg, which is disappointing given the claimed combined figure of 62.8mpg. I spoke to Vauxhall about the situation and was told it takes 8000 miles to ‘break in’ a diesel engine and that 50mpg was ‘acceptable’.’

He goes on. ‘They also told me that they don’t conduct these tests, and that they are conducted at 50mph on a rolling road, so nothing like real life! Reviewers say that the equivalent Golf gets easy over 60mpg, which over 40,000 miles makes a big difference…’

I called Vauxhall and had a chat with a spokesman for the company, citing the mpg figures of Michael and myself. I explained that although the car is an excellent all-rounder that I’d not hesitate to recommend, the fuel consumption isn’t where it ought to be. ‘Remember that these are comparative figures and not delivered in the real world,’ he said. ‘The Astra does have the potential economy. Remember that it is also a 119g/km car, which introduces significant taxation benefits.’ And in the latter, he’s right.

But although most cars will fail to meet their claimed combined consumption in real world driving (I ran a Golf BlueMotion for 12 months in 2009 and averaged 55mpg), amazing fuel figures can be coaxed out of them if you try (I saw an easy 78mpg on a hypermiling run down to Monaco in the same car).

So with that in mind, I took the Astra on a gentle 100-mile cross-country run to see what it could do using those same hypermiling techniques. So, coasting down hills, maintaining momentum at all costs, making sure I’m in the right gear at all times (using the in-built gear change indicator) and keeping to below 60mph, I tried to eke the absolute maximum out of the Astra.

And by journey’s end, I’d manage to average 59.8mpg. The computer had – for a moment or two – displayed an average of 60.1mpg, but settled back down at the merest sight of a hill. It was an exhausting run and because I’d not managed to hit that all important 60mpg average, rather unsatisfying. Especially as I was late for my appointment. And all this, as I’ve said before, is a crying shame because in just about every other way, the Astra’s a very satisfying car to own and drive.

I’ll put this rather average performance at the pumps down to its common-rail 16-valve Ecotec engine, a Polish-built engine made in a Joint Venture with Isuzu that’s been around since the late 1980s, even though it’s received a fair raft of updates along the way. I suspect that the same car with the impressive new 2.0-litre 16-valve Ecotec engine will beat it handsomely in the real world. On paper it’s close – 124g/km and 60.1mpg combined (with stop-start). But on the road, with all that additional power and torque, it’s going to be a whole lot more effortless to drive. And more economical at the pumps.

Keith Adams

62 Comments

  1. A little disappointing, given the claims, as you say – but it’s still absolutely incredible progress that we’re talking about 50 and even 60mpg barriers at all, when even the 40 barrier seemed so economical just a few years ago.
    Probably getting on for twice the MPG that one could have expected of a car of that size and weight in the early 80’s – and hard to think of where else 100% gains have been made in 30 yeras or less…

  2. Keith, I don’t know who Michael spoke to at Vauxhall, but although the tests are conducted on a rolling road, the car follows a cycle that peaks at 120 km/h (http://en.wikipedia.org/wiki/New_European_Driving_Cycle). It certainly isn’t at a steady speed. The tests are conducted by the manufacturer, but will have been witnessed by a representative of a certification agency, probably TÜV as GM’s European engineering is concentrated in Germany. The witnessing certification engineer is responsible for checking the specification of the test vehicle, the calibration of the test equipment, the setting of the rolling road and that the correct procedure is followed. As with any test procedure, it’s important that this is repeatable and comparable to results from other facilities. It’s in the car manufacturer’s interests to get the very best results possible, whilst staying within the rules. Given that the results now determine the tax paid by the customers and hitting the mandated CO2 levels for the car company, then this has meant more care is probably being taken by the manufacturers.

  3. I’ve got a 2.0CDTi 5 door hatch with the 6 speed automatic box – my average over 11000 miles is 38 mpg……I’d be over the moon to get what you got with yours!

  4. I own an Astra 1.6 SE hatch 2 years old with 12k on clock, it’s combined figure is 44.2MPG, and in everyday driving I’m now averaging 40-42MPG.

    It’s a strange car by virtue of the fact if I go on a long run the MPG decreases!

    It is at its most economical on country A roads with cruise engaged at about 48MPG, when it is possible to acheive 47MPG.
    Motorway driving at a steady 70 using cruise returns 36-38MPG.

  5. It doesn’t seem great but diesels do get better with mileage, using premium brand fuel, keeping the tyres a touch over inflated and a regular italian tune-up works wonders too. There are so many factors which affect economy but bearing in mind I could get 50+mpg out of Astra CDTi 888 with a mapped 1.9 diesel which was seriously quick and high 40’s without trying. I get around 62 mpg out of my Audi a2 TDi (with 122k miles) , 48-50 ish out of a SEAT Toledo with the 2.0TDi engine mated to DSG. However in context of the phenomenal 62 mpg Autocar are getting from their Beemer 320D they are all a bit poor.

  6. That economy would be acceptable around town but not with good long runs. I know we don’t like to talk BMW’s on here really but my own 116d easily achieves over 60mpg on the motorway without effort and even around town gives 48-49mpg. This was achieved from day 1 and had just got better as the miles piled on, now at 15k and recently saw 68.9mpg on a good motorway run.

    I wouldn’t say that I try particularly hard to achieve good mileage. OK so the BM has slightly less power but then this doesn’t make any difference in real world situations given peak power is at max revs. Incidentally my wife’s 2011 320d ED also achieves mid 60’s mg on a run and that is both heavier and more powerful than both Astra and 1 series.

    Your results Keith prove the way the figures are calculated are flawed though I admit that both our 2 cars seem to easily achieve their claimed mpg so BMW must be doing something right?

  7. My old Seat Ibiza 1.9 Sdi rarely fell below 50 mpg, even in town, and could comfortably beat 60 mpg on a long journey. This was very much an old school diesel without a turbo and where overtaking had to be planned, but for a far more modern turbodiesel, 49 mpg isn’t good.

  8. You must remember the vauxhall astra is not in the same price bracket as a beemer, all the same, the road test should be in the real world to have a more honest and transparent test, so that protential buyers know what their really buying and not bulling up the mpg as they allways do to make the cars more efficient then they already are.

  9. I dont know about an Astra but an Insignia gives an average MPG which rarely alters and seems to be averaged out over the life of the car and rarely increases on a long steady run. It always stays within 0.1 MPG.

  10. 48 is quite poor. A 2.2d xf will do 55mpg when run in (after 16,000 miles) will do about 45mpg brand new which will get better the more miles added.
    The 3.0d xf i am using at the moment ave 50mpg(cars done 13000)

  11. Wow, these Vauxhall diesels make the >40mpg I got out of a 2.2 Petrol automatic Vectra seem quite astounding!

  12. 60mpg average from a diesel has been common for a few years now. In fact I’ve had several cars over the last few years which have all averaged over 60mpg (and all have shown 70mpg occasionally) : Astra 1.7DTI ECO4 2004-5; Audi A2 1.4TDI (one of the last registered) 2005-7; Corsa 1.3 CDTI 2008-11; Golf 1.6 Bluemotion Technology 2011-12. I’ve certainly seen the previous cars improve with age, but the Golf achieved these figures from new. The outside temperature makes a huge difference – I was averaging about 68-69 mpg during the summer – it is down to about 60mpg now.

  13. 48 MPG is still a hell of a lot more than we could hope for from a smilarly sized car ten years ago. I struggle to extract 30 MPG from my ’03 Astra. Then again, some would say that fuel economy is a waste of life.

  14. A lot of these figures don’t seem too impressive given the cost of the vehicles concerned and the extra servicing/repairs/replacement sensors(!) they seem to need.

    A few years ago, I ran a 1995 Passat with a mighty 75 bhp turbo diesel. Round town or on the motorway it constantly did 42-44 mpg (no trip-computer lies on these!). I replaced this with a Golf TDI of similar era and always got 48-50 mpg with the added bonus of overtaking ability.

    The recent 207 HDI I hired for a week proved no better than the Golf on a long run, had poorer acceleration and cruising speed and was nowhere near the figures claimed, although it must be said it had done very few miles.

    I miss the old-school diesels.

  15. @19 – Phil, is the 207 HDi the same engine that’s in my C3 Airdream, 1.6 DPFS with 99g/km emissions? ’cause I was extremely unimpressed with the Peugeot 406 HDis I tried when they were current, yet this C3 is amazing. Responsive, nippy, consistently >60mpg no matter how I drive it (short runs or motorway, and it predates stop-start by a revision). In gear acceleration is positively quick.

  16. Lets face it 50mpg for a car as big as an Astra estate and with decent performance is actually pretty good going. Only a few years ago this would have been considered a miracle! I think in the drive to get the lowest possible CO2 output during homologation manufacturers are ending up with these incredible fuel consumption figures that can ever only be achieved in laboratory conditions. I guess the official figures provide a comparison between different cars, but dont reflect the actual fuel consumption that can be achieved.

  17. Has Long Term Roadtesting really come down to this? Missing an astonishingly high 50mpg by between 2-6%?????

    To anyone who ever ran a Maestro MDi and a Astra 17D back in the day, this outcome should have been predictable, abiet its still a very, very good result in my opinion.

  18. So to put this into perspective: 48mpg on a Diesel means that it is putting out CO2 at 155g/km. Which means a petrol car needs to achieve 42.4mpg in daily driving – on a run even our old Rover 416 Tourer with the K-series can beat that, but no chance in stop-start traffic to get anywhere close. If you look into LPG the game changes: 29,9mpg on LPG are good enough to match these 155g/km. Which means that my old 1.3 litre Maestro beats the Astra most time in terms of CO2 emissions (and is close in terms of NOx possibly). Surely there is some progress, but in the real world, it is far less significant than the test figures and good marketing try to make us believe. Of course the heavy weight of the cars does not help – at times I wish to sample a Golf 1 with an updated engine, not putting out 180PS, but just the same measly 54 but using all the latest technology.

  19. BTW, looking at the German site spritmonitor.de 79 Astra 1.7CDTi from 2010 onwards average 44.4mpg, but there is also someone claiming 53.3mpg over 136 refills. So there might be a little bit more potential. The average of all BMW 320d drivers of the same age group is about 2mpg better though!

  20. @Lord Sward

    ‘Has Long Term Roadtesting really come down to this? Missing an astonishingly high 50mpg by between 2-6%?????’

    What do you mean? Reporting the facts. Not sure I know what you’re getting at…

  21. I now compltely ignore “official” figures nd just compare figures on whatever car I’m driving with all my previous ones where I have records. As a general rule, cars are getting more economical, but the official figures bear no resemblance to reality and I’m not too sure if they are useful to compare between different makes and models.

    The most economical car I’ve ever driven by the way is a Golf Mk6 1.6 TDI 105 (non-Bluemotion) which I hired in Fort Wiliam this year which got hammered across the Highlands. Yes, there were some long economical flat bits, but there were also some proper hills to balance out. Overall? Bang on 60 mpg with a best of 72 mpg. I’d say that this is about the ultimate trade off between power and economy; a smaller, less powerful engine would probably have to work harder in those conditions and a larger, more powerful one could be a aste. Also in places like the Highlands, range is the big issue. There aren’t too many petrol stations around!

  22. Unfortunately the legislative requirements and tech required to meet EU5 and 6 emmission regs are having an adverse effect on engine economy, especially for diesels. My 1986 Passatt 1.6tdi estate gave 50+mpg from 75 horses as did my 1992 Audi 80 with the then new 19 direct injection TDI 90 engine. If legislators backed off and allowed the manufacturers to concentrate on achieving economy we would probably be getting better fuel consumption from all cars. Having said that the ‘real world’ economy of BMW and the latest Mazda Sky diesel engine (which does away with a lot of the expensive solutions used by most other manufacturers by adopting a low compression and very tight manufacturing tolerances solution) shows it can be done. The legislation is adding so much cost to the manufacturing process we are unlikely to see many small diesel engined cars in the future and it is probable cars below Golf class will only have a petrol engine range. The VW ‘Up!” will not have a diesel option and neither will the ‘Adam’.

  23. I question to accuracy of car computers when it comes to fuel consumption. Comparing the actual fuel consumption (calulated manually from full tank to full tank over many cycles) shows the car computer to consistently inflate the mpg figure by around 10%. This is on a 2006 X-Type Jaguar but given that the computer measures how much fuel has been consumed and how far the car has gone, I find this level of inaccuracy disappointing. Do we all give too much credence to what the digital display is telling us?

  24. Are you just going by the trip computer? I don’t pay any attention to mine and only go by what I put in and calculate.

    I also think that the CircleL 1.7 was always a bit disappointing in the mpg stakes, and I don’t think it matters what they do to it. I had a 2006 Astra-H 1.7D (Variable-vane turbo, Nippon Denson common rail etc.), which was supposed to be better than the Rover 420Di it replaced, but it wasn’t. Based on fill-up records, these cars, my Maestro before it and my current Honda Civic, achieved:

    Maestro 2.D (1994) 57.0mpg over 101k miles
    Rover 420Di (1999) 53.1mpg over 193k miles
    Astra-H 1.7D (2006) 51.7mpg over 117k miles
    Civic 2.2iDTEC (2012) 61.6mpg over 13k miles (so far)

    I have high hopes for the Civic, although it was flippin’ expensive! One wonders what a Rover G-Series might have achieved in an RD/X60. Sigh….

  25. @ Adrian – 27

    Does the mazda engine have DPF or not?

    Due to my living in North West Northern Ireland (no motorways at all, maximum journey time of 1 hour) I would be VERY wary of buying a modern DPF diesel.

    If you can tell me of an estate car that beats 40mpg (in my sort of driving conditions), has a bit of character and has similar spec to a ghia ford of old then it will be my next motor.

    otherwise it’s looking like a 318i touring 🙁

  26. @ Keith Adams;

    I’m quite sure your report is entirely and ruthlessly correct. However to title what would otherwise be a faultless report as “Thirsty” because it falls slightly short of 50mpg is in my opinion, mean.

    Also from my experience if you thought the Astra could do 50mpg in real-world conditions you were being naive. They couldn’t do that with the same engine in a significantly lighter bodyshell running with no emissions kit back in the mid-90s. Affordable efficiency can never outrun basic physics.

  27. The Rover’s dear old L-series, never mind the world beating MDi delivered better mpg! Economy was never a GM derv strong suit. What was and still is a GM strong suit is cost of purchase, eventual residuals and running costs.

    ‘Real life’ fuel economy is often bandied about by journalists as by a long way short of publicised figures, but you cannot blame manufacturers for that, indeed, its in our interests that such figures are wildly optimisitic.

    You cite the VW Golf Bluemoon delivered better mpg. However, you can buy a Astra 17 derv for many, many thousands less than the Golf in the ‘Real World’ and the cost of service items from the main stealer is also likely to be cheaper. Doing the full set of sums would see the Brit-built GM cheaper to purchase and run overall I firmly believe.

    Lets add up real world purchase price and real world MPG to get a genuine cost-per-smile. Although ultimately driving a diesel is unlikely to raise a smile.

  28. Trying to crack those elusive MPG figures simply makes driving stressful and mind numbingly tedious.

    I tried all that lark with my Civic ending up ignoring the fuel computer and just honing my techniques especially in city traffic to eek an extra drop or three

    In the real world its all about whole life costing which bearing in mind the Astra tourer is maninly going to be a fleet purchase, WLC is all your average fleet manager will be intersted in.

  29. My 75 CDTi was regularly giving mid / high 50s to the gallon back in 2004.

    48mpg 9 years on seems pretty poor. Even my Proton Gen-2 hack manages mid 40s easily on unleaded and 38+ on LPG.

  30. @ Tim,

    I wish my 75 would see mid to high 50’s

    Current mixed mode driving (maximum journey of 40 miles) without much in the way of traffic jams is resulting in early 40’s and thats with a brand new MAF

    Not ideal. Mind you it is an estate with 127,000 miles on it

  31. My old Golf 2.0TDI trip computer used to over estimate the average fuel economy figure (and also gave crazily high values for the range on a full tank). It had an issue with the cruise control and as part of the repair the garage updated the software on the trip computer – it was far more in line with my own calculations after that.

  32. “What was and still is a GM strong suit is cost of purchase, eventual residuals and running costs.”

    Tell that to the T-reg Astra Envoy Diesel estate I had in 2006. I paid £650 for it, with 72,000 miles on the clock. So, from new to £650 in what, 8 years? At 99,000 miles, the diesel pump threw a fit – the car just died. Secondhand wasn’t an option without a dealer trip, new was in excess of £800… the coded system ensured fixing what we suspected was a faulty shut off valve was incredibly expensive.

    Oh, and a wheelbearing that went on the back was a whole hub unit. Cost wise, pretty evil, though as a DIYer without a hydraulic press, it was a doddle to swap over at least.

    My 300C – which I’ve been abusing for the 16-mile round trip to Nuneaton station I do twice a day at the moment – is giving me 23mpg in these conditions. I don’t think that’s bad, for a 5.7 it’s very impressive!

  33. When I was rich and famous I drove a V8 Discovery. Highly tuned, it delivered between 9-12mpg. I saw it as my way of giving back to society in which I’d been so richly rewarded within. Indeed my local Health Authority wanted to name the new children’s ward in my name I’d paid so much tax on the sans plomb. Then there was the glorious V8 tune which enriched the streets.

    These days I drive a TD5 Discovery and the country has gone to the dogs. I simply don’t believe in coincidences.

    For the sake of 2mpg, you can see George Osborne reduce the country’s debt, the good people of Cheshire keep their jobs at GM’s Ellesmore Port Plant and finally, you’ll be able redeem more Nectar points come the Christmas shop.

    Think on folks….

  34. 30: I am not sure but suspect it does. Should be easy to find out, the new engine is fitted in their new SUV (CX5?).

    However as for using the trip computer to calculate mpg it is only a guide at best. I always do brim to brim calcs which n my A2 normally show a slightly better figure. However i agree with Keith the difference between 49.6 (unnacceptable) and 50.1 (acceptable) mpg isn’t worth the argument. And for me diesel isn’t just about mpg, it’s also about torque and drivability which I prefer to the vast majority of petrol engines (my 944Turbo being an exception!!)..

  35. @Richard Kilpatrick

    Always been a fan of 300Cs, been keeping them in mind if/when the Honda ever dies.

    Not bad MPG, Im getting not far off that on a 2.0 vtec. LPG at 75p a litre would give diesel running costs 🙂

  36. My old 2.1 TD XM Exclusive Auto would do 55mpg without resorting to hypermilling, I wonder what it would do had I tried.. Progress seems to be minimal in comparison

  37. Trip computers I wouldn’t trust them as far as I could throw them. My old A4 2.0TDI used to overestimate the range left (700 miles on a full tank, but realistically it was more like 550). The A3 1.9TDI I have now reports the remaining range at zero miles yet the fuel gauge still hasn’t gone into the reserve zone.

  38. @23
    I have a plot to fit the 1.6 FSI motor to my Mk2 Golf GTI to see just what the result will be, on papper the power figures are very close between the FSI and the EV it is currently fitted with. Be very interetsing to see how it compared with the 1.9 TD version belonging to the ludites down the road.. Although I was getting very close to 40 MPG from the EV

  39. Proof indeed that manufacturers ‘claimed’ mpg is total tosh. I had a feeling they were done on a dyno in controlled conditions. How about forcing these lot to to ‘real world’ mpg figures? I bet the CO figures are a joke too.

  40. I have a 1.6 bluemotion Golf cabriolet and have done nearly 20k and my average mileage has never got above 52mpg. I know that the cabriolet is very heavy and has poor air flow but woudld have expected better economy.

  41. Hi all,

    Thanks to Keith for publishing my comments. Various people have said on here that what the manufacturers claim and what they are in real life is the frustration. My car before this Astra Tourer was my dads 1998 modified 5 speed BMW 318TDS estate which you seriously had to push up a hill until i got a PSI box which took the BHP from 90 to about 100!! In that i got circa 45 mpg’s over a similar journey profile to what i do in the Astra Tourer and it felt really sluggish. I am in the midst of trying premium grade mobil engine oil and also Shell V power. And it seems that might make a difference. Dont get me wrong i dont obsess about MPG but when you are putting in about £50 a week into the car it does become a talking point…. Also people mention on here about the speed, on mine this doesnt seem to make a difference (ie 60mph versus 80mph) though i have stopped using cruise to increase the speed and just use it to hold the car speed on the road.

    My frustration is that you get a car and i naively hoped i would get good economy but it’s not been like that. Honestly it seems that only the germans come close to what they claim….

  42. Just watching a repeat of Fifth Gear from 2008/9 where they tested the Suzuki Splash the 1.2 petrol and the 1.3 diesel. The petrol managed 45 mpg on their test run, the diesel got just 41 mpg. The petrol model is also £1000 cheaper to buy and at the time petrol was 15p a litre cheaper.

  43. Well looking back over my cars I must say diesel engines are no better than 15 years ago

    1993 fiat tipo 1.9 Ted six never went below 45 MPG and on runs over 40 miles would returns 55mpg all day long

    2002 vauxhall vectra 2.2 dti 46 running around 52 on a run 2005 rover 75 cdti 131 38 MPG running around 51 mpg motorway 2007 vauxhall vectra 1.9 cdti 150 40 MPG running around 49 on a run
    2010 soda superb 170 tdi 28 running around 47 MPG motorway (bit sad about this was expecting better.)

    So as you can see from my experience things have not got better intact dpf have increased fuel consumption have a few friends who have had there dpf removed and they say HP is up and
    Fuel economy is better by about 10mpg

  44. Official figure are on a rolling road?????

    What a joke!

    That means aerodynamic efficiencies and weight of the vehicle have no input into official figures.

  45. I can’t see how they’ve been getting away with testing cars on rolling roads for so long.
    For starters there’s no wind resistance or drag or a rolling road (unless they simulate it, correct me if I’m wrong) hills or grooves and ruts you get on a road to knock the MPG down.
    Factor in how they’ll be no cyclists or other hazards that you’ll HAVE to brake for, even if very lightly and it becomes even more of a farce…

    @ Richard Aucock. Just to confuse you: http://www.diynot.com/forums/viewtopic.php?p=257693

  46. Update – I’m currently smoking around in a 2.0CDTi Astra Sports Tourer and the early indicators are that it’s more economical to the tune of about 6-7mpg…

  47. Interesting point about the 2.0 litre Keith. 6 – 7 and increased power is kind of a no brainer and have to admit am a bit gutted driving around in the 1.7! Also about the DPF, wonder if it can be turned off as that would make a big difference.

    Just filled up this evening with the following stats. 905 miles, 82.20 litres, 51.37 mpg’s all with V Power. This was a part fill last weekend and then full tank this evening, it’s not an 84 litre tank LOL! Another tank of V Power but seems that this makes a small difference though not enough to justify the 9p increase per litre. Car feels better to drive with a bit more power but shell standard wont be far behind me thinks!

    Thanks for all the hints and tips!!

    Cheers

    Mike

  48. I have the almost the identical car here – same colour, same engine, same body, same spec……you get the jist.

    My TANK average for my commuting weeks is never below 51mpg and I get over 610 miles out of a small 56ltr tank. One commuting trip (94 miles there and back) gave me 53.6mpg with 57ish on the way to work. Remember the car weighs 1500kgs people…that’s more than an old BMW 5 series (up to 2002 range). Town driving never gives me less than 40mpg. I don’t drive like a saint either and downhill parts of the motorway in Scotland it can give me over 70mpg at ‘fast’ speeds (if you get the jist…again).

    I’ve down 40,000 miles now (in 2 years) and the only thing that has gone awry is a sticking rear disc (and I would love to know how many VAG group cars readers have here that have had so few things go wrong!). I can’t fault it to be honest – the ability to transport massive amounts of luggage/crap in the boot and drive so well (and look so good) is a real testament to how well designed the car is.

  49. Sorry actually I have mis-read the other posts. I have the 2.0 CDTI 160bhp. MPG figures def look good now!

    D.

  50. I am furious with my 2010 1.7Cdti Touring – it averages 42MPG…it a good solid car and a workhorse, but this mpg is unacceptable.

    I had an old 2001 Mondeo estate with the DuratorQ engine (Transit..) and it gave 47mpg all day, and a 2001 2.0DTi Vectra which gave 53mpg all day

    Vauxhall – this is a disgrace

  51. I assume you have examined your car for faults such as as a dragging or binding brake or poor wheel alignment and found nothing amiss.

    High mpg returns requires keeping the throttle pedal at a constant setting while at a cruising speed, every movement of the throttle pedal requires the ECU to recalculate injector settings. Keeping the pedal constant lets the ECU “home in” on a low fuel consumption setting, it can take 10 to 15 seconds to allow the ECU to trim back the injection timing for maximization of fuel economy. Therefore is your driving technique steady as she goes or, cut and thrust?

  52. Even worse, I read that fuel consumption is not directly measured, such as measuring quantity consumed over distance.
    The exhaust emissions are measured and the fuel consumption deduced from those readings

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