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Albion

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Albion last won the day on August 11 2018

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  1. If they use the engine for all the significant propulsion (aided by electric motor for acceleration) then, other than the regen as a result of braking, that electrical energy has to be replaced by charging the battery via the large alternator/starter motor. The drive to the alternator uses energy generated by the engine and therefore adds extra load to the engine thus adding to the fuel consumption, and it won’t be 100% efficient in doing so, so how exactly given the laws of physics do you get such claimed economy under normal driving conditions (excluding regen braking of course) considering much of that mileage won’t be decelerating? I’m really interested to know how that works with the driving pattern of Mr Average. Roger
  2. Back in the late 90s when I was working for Rover Cars I know that they got hold of one of the early Prius’s and tested it on the rollers and told me that it did nothing like the claimed mpg. Whether things have improved since then I have no idea. I only have one friend who drives a hybrid, an Audi, so when I get a chance I’ll ask him what he gets mpg average and how long a charge lasts before the engine has to kick in. Roger
  3. My thoughts on the electric vehicle situation is this: 1. IMO there isn’t enough public charging infrastructure in place now and I frankly doubt that it would keep up with any explosion in EV sales. 2. You live in a terraced house with on street parking. Do you trail the charge lead across the pavement causing inconvenience for pedestrians and the visually impaired. 3. Even now I often see the dedicated charge point parking slots being occupied by non-electric cars. How will that be handled not only now but also when many more charge points take over existing parking bays. Roger
  4. Agreed but that wasn’t the implication of the article. I also reiterate that I never saw any test vehicle with bald tyres on the test track or in the dynos. There is no argument that the engineers will do their utmost to get the best results (no-one should be surprised at that) but I have never witnessed the extent of out and out cheating that is implied in the articles. Roger
  5. NZ is lovely. We have toured the South Island and loved it for the scenery etc. We are now touring the North Island which doesn’t quite have the stunning scenery. However the penalty, particularly for the South Island, is that it is still an active earthquake zone (Christchurch is still a long way from fully rebuilt for example) and some of the roads are vulnerable to slippage. We spent a couple of days in Fox Glacier and then drove out along one of the mountain passes only to see on their TV about a week later that 300 metres of that very road had collapsed and fallen away due to the heavy rain and other conditions. That resulted in Fox Glacier being totally cut off and accessible only by air thus crippling the Fox G economy which is totally dependent on tourism. We love the place and the people though. The attitude and friendliness of the service staff is excellent. Food and clothes are expensive though. Petrol is very slightly cheaper than the UK but definitely cheaper on the North Island compared to the South (by about 15 cents from what we have seen so far). Roger
  6. Oh sod it I have tried to reply twice now on this iPad from New Zealand pointing out the errors or exaggerations in each of your links one by one but have lost my incomplete reply twice now and cannot be bothered to retype my huge answer all over again point by point.. I will though reiterate a classic from one of your Independent links that states that the emissions test cars are fitted with slick tyres and have things like wing mirrors removed to reduce air drag during the emissions test. I have never seen an emissions test car fitted with slick tyres ever. They use tyres that have been run in but not slick. The test is overseen by an official from the VCA to ensure that the legally required conditions are met, even tyre pressures are cross checked. Then the classic!!!!!…wing mirrors are removed to reduce air drag! If you can tell me how removing wing mirrors reduces drag on a car that does it’s test statically on a rolling road then I will willingly accept every one of your points 😂. Of course they use the best cars with the best test drivers but they want to achieve the best results , wouldn’t you in their position? Another link states that cars are tested from cold. That is not strictly true. They are tested from an un-started condition but at a temperature of 25C IIRC. The cars have to be stored in what was known as ‘The Soak’ at Rover which is a storage area maintained at a constant temperature for at least 24 hours before testing to achieve a stable temperature. They are then moved onto the test rollers using an electric recovery trolley and are not fired up until the test starts. You do not seem to understand how a car is developed. The Powertrain Calibration Engineers start the development of the tune maybe up to two years in advance of the model’s release. They know what Euro standard they are aiming for long in advance of the model’s release because the EU sets the changeover dates well in advance. So, let’s take the case of a car aiming to achieve Euro 6. The engineers gradually improve the tune attempting to beat the limits by as great a margin as they can while also achieving as economical an mpg figure as possible AND at the same time ensuring good drivability (it is of no use what so ever having the car run very lean to achieve emissions and good mpg if it is so lean that it hesitates pulling away from junctions or lacks full power). All this is done to achieve the target Emission’s standard (Euro 6 in this case) and not some real world driving test that wasn’t even thought of, never mind legislated for, at the time that development started. You are comparing apples with oranges and saying that they aren’t the same. I still maintain though that the best testing will be a rolling road test to a fixed road cycle to compare one car with another accurately AND another real life road test to ensure that the vehicles are not exceeding the legislated limits on the road. The road test will, inevitably, have some variation in results though because, even with an identical route, the traffic conditions, traffic density and weather conditions will vary significantly. Roger
  7. Unfortunately your Financial Times article needs a subscription to read so I can’t do that. Certification against new emissions standards is done towards the end of the development process not on a car by car, prior to sale, basis. I certified the OBD part of the process for the 2.7 diesel in the S Type and the XF so am fairly aware of the process involving the UK VCA (Vehicle Certification Agency). All manufacturers register cars from new and put them out into their management lease fleet or as demo models. It’s a way that they boost their sales registration figures and convert new cars into low mileage second hand cars that can be sold cheaper than new. Proof of that is that a friend of mine from my old Ford days gets a retired employee pensioner’s lease car which has to be returned after only a few months. I am not denying that diesel sales have fallen partly due to our Government’s sudden about turn on diesel and the massive downturn in the Chinese market (for JLR certainly) but I think you are exagerating to blame all of that fall on a huge failure of diesel cars to meet emission’s standards. The list that I provided is entitled ‘The list of Euro 6d temp diesel cars expands considerably’ and so while I am not claiming that it covers every single diesel car it does contain a significant number and especially many of those larger prestige cars that you imply are major 6d temp failures. I would still like a list of those manufacturers that have been known to ‘comprehensively fiddle Euro 5 & 6 tests’ though and I mean proven and not just gossip. Roger
  8. You frequently make the assertion that Euro 5 and 6 emissions tests were comprehensively fiddled. Please list all the manufacturers, other than VAG, that have been discovered and publicly named for doing so. You also say that the 6d Temp testing culled out the diesels because the earlier tests were rigged and yet this link gives a huge list of diesels that comply with 6d Temp so it does give the impression that your anti diesel stance could be slightly influencing your statements. https://www.fleeteurope.com/en/connected/europe/features/list-euro-6d-temp-diesels-expands-significantly?a=DQU04&t[0]=Euro 6d-TEMP&t[1]=RDE&t[2]=ADAC&t[3]=WLTP&t[4]=Diesel&curl=1 I do not deny that the RDE tests are due to make things much harder for diesel emissions particularly for NOx but, and I have said this before many times, the tests on rolling roads are very specific (but complying with European regs) and driven to the required very specific performance curve. Manufacturers use their best cars, their best test drivers etc in order to achieve the best emissions coupled with the best mpg (and you can’t blame them for that). Real road conditions can never be, or are intended to be, the same as the rolling road tests. In my opinion the rolling road tests will be best for car to car comparison and the RDE tests best for real life emissions indications. During my my career in Automotive development (specifically OBD) I worked on the Rover 75, BMW Mini, Jag X Type, S Type, XF, XJ etc and being OBD I worked very closely with my Powertrain calibration colleagues as the two functions are very closely related on emissions control. During the whole of that time I never heard the slightest hint that they were fiddling the results. In fact the only time a known fiddle was mentioned to me was regarding an Italian sports car. Also, what you may not know is that manufacturers often swap cars with others (or sometimes purchase them normally). In that case as they run tests on the competition’s products don’t you think it would get out if the opposition was fiddling emission’s results? I don’t think you can imply that problems with Jag engine durability may be due to fiddling on emissions, why could it not be poor engine design? Roger
  9. Whatever you may think, the regen process satisfies European Euro 5 emission requirements and with the addition of Adblue satisfies Euro 6. From memory the regen emissions are taken into account for the total emissions to meet the rolling road based emissions tests. What will happen on the real road tests that are now included I’m not sure as that is well after my time in OBD development and emissions testing knowledge from my Powertrain colleagues. Roger
  10. No you won’t get a warning if it is a routine regen under suitable road conditions. The warning on my car is when it would like to do a regen but the conditions are not right and it asks you to achieve those conditions soon. My Euro 5 Freelander never needed to give me a warning and you could never tell when a regen was happening. My Euro 6 Disco Sport also is undetectable when a routine regen is being carried out but has, just once, warned me that the DPF was heavily loaded and recommended a mininimum of 40mph for 20 mins. I did that with slight speed drops during the 20 mins around roundabouts on my test route and I suppose the regen occurred because the warning disappeared however I wasn’t again physically able to detect it taking place even with my knowledge and skills of many years in the automotive industry and the garage trade. My driving route characteristics haven’t significantly changed between the Euro 5 and Euro 6 car (mainly longer distance and higher speed use) so I was surprised to see the regen warning come up for the first time ever. Roger
  11. But from what I was told at the time and what I have seen on my Disco Sport you should get/do get a message on the instrument panel saying something like ‘Regen required, exceed x mph for y minutes to achieve’. So if you continue to ignore that message it shouldn’t try to regen when the conditions aren’t right in my opinion. Then, if you do ignore it then it is a workshop forced regen if that can be achieved. You seem to be saying that the low speed regens occur without having warned the driver in advance. I do agree though there is no excuse for a garage not to investigate the oil quality and levels before trying a regen of some sort. Even I kept an eye on my oil level long before it went in for service looking for any indication of increasing oil level etc but the check only showed 1.5% contamination according to the dealer. Roger
  12. It’s not actually injected as fuel into the exhaust stroke as such. Piezo-electric injectors are fast enough to be able to inject several times during the normal compression/combustion cycle. What they do for DPF regen is to inject very late in the combustion cycle which sends a partially combusted but still burning charge down the exhaust and into the DPF thus heating the DPF and burning the larger stored particles Into combustion biproducts and finer particles which are then exhausted to atmosphere. It occurs only every few hundred miles and, in the case of this process, only when up to specific temperature and speed conditions. Roger
  13. On the first service on my LR they did an oil dilution check and it was 1.5% on my low mileage vehicle. I believe it might be part of routine service checks at the dealer. Not sure if it is the same for Jags though as I haven’t got one. Roger
  14. One thing has occurred to me that might explain the differences in VAG regen and others of my experience and that is how close coupled the DPF is to the engine exhaust manifold. On some cars the DPF can only be fitted at a distance and hence runs cool and so the only likely regen possible is with an afterburn caused by late fuel injection. I have since read though that some manufacturers have been able to raise the temperature of the DPF by getting it as close as possible (or even possibly attached IIRC) to the exhaust manifold. Perhaps that could explain the difference but I stress I have no knowledge of the VAG positioning. Roger
  15. The regen occurs (and I would call that active regen) because fuel is injected late and is sent as an after burn into the close coupled dpf (one of the known problems on some vehicles is that the dpf is not close enough to the engine and tends to stay relatively cool). When the pressure sensors detect a significant pressure difference across the dpf (i.e. clogging) it starts a regen procedure provided the road speed is sufficient to have elevated the baseline dpf temperature adequately AND enough to prevent drivability issues being apparent to the driver. Then the late injection sends the afterburn down the line to burn the particles into much finer particles and eject them, thus cleaning the dpf matrix core. In the workshop it is possible to activate what I would understand to be a passive regen but only with intervention using the manufacturer’s service software. That was certainly what happened when I was working alongside the Powertrain guys when I was at Jags. Whether things have changed since I can’t be sure. Roger
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