Sounds similar to diesel now with additional complexity added to the electronic ignition system controlling this new technology too.
great :-(
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Of course another reason why diesel engines used to be harder wearing was the simple fact that diesel is a lubricant in itself, petrol acts as a solvent washing oil off the cylinder walls.
Modern fuel injection systems keep engines running slightly on the lean side minimising bore wash, also fuel is shut off when the throttle is closed in gear, with fixed-choke carburettor engines this would mean a period of running incredibly rich undoubtedly causing bore wash. The better FI systems allied with advances in metallurgy and manufacturing tolerances mean petrol engines can now last (mechanically) huge distances.
The catalytic converter has done more damage to the advancement of petrol engines than anything else. It halted, at a stroke, the development of ultra lean-burn engines and at the same time decreased fuel economy by nature of a deliberate obstruction in the exhaust pipe. Think about it, go back to the 80s and look at the Maestro 1.3 - a petrol car with an ancient engine capable of practically 60mpg on a run - have we REALLY gone forward? Had we not gone down the catalytic converter route enabling manufacturers to carry on producing the same old tired four stroke petrol designs we would now have 100mpg lean burn (possibly compression ignition) petrol engines. The world leader in lean burn engine development was Rover, The K-series was originally designed to be a disposable lean burn unit (sadly they kept the disposable bit!) - the forced adoption of the catalytic converter killed that project stone dead as lean burn engines and a cat are mutually exclusive.
Had the greenies not been fooled by the huge bodge of dangling a bit of toxic waste off our exhaust manifold to hide inherently polluting engine designs. Petrols would be streets ahead of diesels, yes lean-burn had a problem with high nitrates etc - these problems could have been fixed and we'd now be doing 100mpg in petrol powered cars.
Edited by SteveLee on 18/01/2010 at 14:35
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I would agree that the politicians were hoodwinked into catalytic converters by the auto industry as a means of reducing pollution for the absolute minimum in redesign. We have collectively wasted millions of gallons of petrol as a result of this - which denied us the lean burn route.
The K series engine is best forgotten as the last feeble attempt at design by a non-engineering organisation. Perhaps if they'd tested it they might have not bothered to inflict it on the motoring public.
Unfortunately, the diesel is going the same way as the catalytically constrained petrol engine. Diesel particulates are sometimes visible in their worst manifestation as smoke and hence demand instant attention by the non understanding politicians. (Compare wind power and wave power - you can see windmills but not the apparatus under the sea - so the politicians go for the visible "solution" so everyone thinks they've fixed it).
The DPF will do for the diesel what the catalytic converter did for the petrol. It discourages the running of a diesel engine at light load - the very conditions under which it gives the greatest gains - and reduces its overall efficiency at all output levels. Regeneration of the DPF results in a higher CO2 output per transportation task due to soot burning and extra fuel is needed to accomplish this. There are other developments which can reduce particulate emissions in the diesel engines and their reduction is a right and proper goal.
The unholy combination of non-understanding politicians appeasing the chattering classes and the auto makers wanting to sell as many units as possible for the minimum retooling costs means that we will once again be paying lip service to the environmental aspects of the problem and wasting countless litres of valuable hydrocarbon fuel.
The diesel is still the most efficient IC prime mover for absolutely basic thermodynamic reasons. We should nuture its design using the best technology at our disposal - not wreck it with a short term bodge.
659.
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The K series engine is best forgotten as the last feeble attempt at design by a non-engineering organisation. Perhaps if they'd tested it they might have not bothered to inflict it on the motoring public.
I don't even know where to start with that one! The company that gave the world the first viable commercial jet engine is not an engineering company? Rover may have had nothing in terms of budgets but innovation and engineering excellence were not lacking. Just take the Maestro/Montego, history says they're rubbish. they had the world's first flat pack electrical wiring (now universally adopted) the worlds first production car with a bonded windscreen increasing structural rigidity whist reducing bodyshell weight (again adopted by EVERY car manufacturer), inventor of electric power-assisted steering, stolen by BMW and sold to Bosch. Yes the K-series had its problems but it is an excellent engine in engineering terms, half the weight of most of its competitors ? built on the kind of budget that wouldn't keep Mercedes in ashtrays. Strange how BMW kept the patents of such a bad design. Just about all F1 engines are through-bolt designs ? rubbish engineers those F1 folks. In the mid 90s BMW's first alloy blocked 2.5 six was a disaster ? 10 of thousands went bang or suffered from heavy oil consumption and were hastily replaced by BMW ? often secretly and the problem was kept quiet, if this was a Rover it would be on the front page of every motoring rag. By all means knock BLMC's awful Trotskiest workshy workforce or the stupid old men stuck in the past on the board making poor product decisions, but the company from an engineering point of view have an incredibly rich history, one that most car companies can only dream of.
>>The diesel is still the most efficient IC prime mover for absolutely basic thermodynamic reasons. We should nuture its design using the best technology at our disposal - not wreck it with a short term bodge.
It's also an inherently dirty fuel from a pollution point of view (real pollution not plant food emissions) petrol is a better bet until electric or hydrogen/electric power is developed sufficiently.
Edited by SteveLee on 18/01/2010 at 16:25
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K series:
Fitness for puropse lies in the detail.
659.
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I had the 1.8 K-Series in both VVC and non VVC forms, both were refined, torquey and powerful for their time / displacement. Probably the fasted warm-up of any engine I've driven, I liked them, although I didn't keep either car long enough to experience reliability problems...
Surely companies such as Lotus and Cateram must have selected these engines over GM or Ford designs back in the 1990s for a reason (price maybe but also their tuning potential perhaps ?)
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I agree, Rover were never short of innovation. What they never bothered to do though was develop this innovation properly before releasing it to the public. How many of their cars repeated the same old story? Clever design, released before it was developed properly, broke a lot, problems got fixed, later cars superb, nobody cared, heroic failure.
In the K's case, had they left it as the 1.1 and 1.4 litre lightweight runabout engine it was designed as, and not stretched its capacity and installed it in ridiculous things like 1.6 tonne 4x4s, I suspect it would be remembered as one of the greats about now. You cannot knock its power to weight ratio, compact dimensions and astonishing efficiency. Neither unfortunately can you deny the incredible frustration and expense this engine has brought on so many of its owners. But I agree, the fundamental design, in the context of the original design brief was fabulous. Unfortunately, the very design features that made it work so well in a small, light car made it completely unsuited to the larger, heavier, higher output applications it was later adapted to.
One of the great injustices with the K to my mind was the VHPD variant of the engine which quickly became renowned for sticking conrods through the block, expiring in clouds of steam, and generally displaying all the longevity and robustness of a 60's Italian supercar engine. Rover were not even consulted on this engine, much less had any hand in its design, yet its numerous failures only added to the engine's reputation for fragility, and impacted Rover's reputation directly. I cannot somehow imagine BMW allowing a third party to pink fluffy dice their engines, reduce them to fragile, lumpy, horrible wrecks, and then let the mud from the repeated blow ups dirty their name.
Edited by Webmaster on 19/01/2010 at 01:21
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A newbies' question: Is the aforementioned K-series engine (which seems to attract praise & opprobrium in equal measure), the same K-series that was used in the last (up to 2005) installations of that name?
I'm thinking of the 1.8 petrol unit (of HGF fame) used in the Rover 45/75 in particular.
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I'm thinking of the 1.8 petrol unit (of HGF fame) used in the Rover 45/75 in particular.
Yes it's the same engine. the last of them were finally cured though, new type of head gasket and a strengthened crankshaft cradle. The K was never designed to be a 1.8! Greedy bean counters stopped Rover producing a bigger version and stretched an already small highly advanced engine way beyond what was sensible.
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>>Yes it's the same engine.
Thanks for the response.
I was idly looking around for a runabout & was quite taken by a Rover 45 1.8 of 2001 vintage I saw - I imagine this is a bit too early for the final (fixed) engine version though.
Back to the OP's question - my gut (as opposed to limited technical) response is that diesels of any age (subsequent to the 'old' school type that is..) are a liability waiting to happen unless they've had impeccable provenance and/or known history - c.f Humphs legendary Mondeo 11 diesel.
It's also becoming obvious that the inability of gearboxes & drivetrains to contain the fierce torque of diesels (which seems to have led to DMFs & other 'fixes') is another reliability liability mitigating against long & efficient vehicle life.
All in all though, it's probably a moot point anyway (sadly!) - most IC engines are doomed, it seems, by the electric engine or its familiars.
Edited by woodbines on 18/01/2010 at 17:54
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"Back to the OP's question - my gut (as opposed to limited technical) response is that diesels of any age (subsequent to the 'old' school type that is..) are a liability waiting to happen ......"
That's exactly my feeling, rightly or wrongly.
Frederick
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At work we have a variety of John Deere and Ransomes machinery for grass cutting, leaf blowing etc. The diesels in these are of the old style mechanical injection variety. They get worked hard all season in sometimes very dusty conditions, they go in once a year for a standard service, they come out and do the same thing the next year. They never have engine problems, maybe a cooling issue or the hydraulics fail but the engines are solid.
If I could own a diesel car currently available that could take that kind of abuse and still work properly, I would love one. I know that the above are not suited for cars, but the point I'm making is that as an engine designed to do the job, they are brilliant.
Not so sure that diesels are better as car engines over petrol. They don't seem to like being made more and more refined, they throw their toys out of the pram!
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Not so sure that diesels are better as car engines over petrol. They don't seem to like being made more and more refined they throw their toys out of the pram!
Power outputs have risen dramatically too. Go back to the late 90's and you would typically see 90 bhp from a 1.8-2.0 diesel with maybe the odd 100-110 bhp "performance" example. Now you're looking at a 140 ballpark with 180-200 for the odd "performance" example.
I love the delivery of diesel in every day driving. Our Golf feels properly fast in certain conditions in a way that an equivalent output (130 bhp) petrol equivalent never would. They also have a fantastic ability to shrug off weight as if it's nothing. I can think of nothing worse than a big estate car or mpv with 130-150 bhp petrol engine. With a diesel, it's almost fun.
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Our Golf feels properly fast in certain conditions in a way that an equivalent petrol ( 130 bhp) never would
What diesel is this DP? A mkIV PD130?
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What diesel is this DP? A mkIV PD130?
Yes. Of course it's not a fast car, but it often feels like one. And that's almost as much fun. The way it goes from 40-80 in 4th still makes me laugh out loud sometimes.
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Good post DP, I was going to mention the engine was stretched far beyond it's original design criteria but didn't want to make my long post even longer! In its original capacity it IS a great. The decisions were all about budgets not engineering. Most people also forget that the Rover V6 put in the 800 was more powerful, fuel efficient and reliable than the duffer of a Honda unit it replaced, a great engine until, again, this engine was pushed far beyond original design criteria a-la the other K-Serieses and started to suffer reliability issues when fitted to Landies etc. The Rover 214 made the Honda-engined 216 obsolete, the 214 was just as quick as Honda's 1.6 and was more fuel efficient.
IC
The reason Lotus etc used the K is because it was by far the lightest production engine of its capacity in the world. The excellent Rover VVC system (far better than Honda's equivalent which wasn't fully variable) gave the Rover 25 Gti better in-gear acceleration than a Golf VR6. If you can find a clean 125bhp Rover 25 - buy it - it's a cracking car before they over-tuned it and ruined drivability.
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Re the "power" of modern diesels - what power? We are comparing turbocharged diesels with normally aspirated petrols. people ignore the fact that all these so called wonderful engines are turbocharged - it's the turbo making the power not the inherent "power" of a diesel. A 2 litre turbocharged petrol engine could easily make over 250bhp with tree pulling grunt from tickover. Like for like, petrols make far, far more power than diesels, but diesels are normally turbocharged and generally have to be to be competitive as they don't rev and therefore cannot make decent power without one.
So in a nutshell a modern diesel is giving you the impressive fuel economy of a diesel when cruising along, when you put your toe down, a turbo is there to give you power when you need it. If diesels are so good, take the turbo away and you're left with 80bhp chuggers that sound like an old barge. As Honda have shown 100+ bhp per litre - with reliability - is possible from a normally aspirated car petrol engine, anything like that from a n/a diesel is impossible. Stick that in yer waste gate and smoke it diesel-heads! :-)
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Well if petrol cars need to get more fuel efficient - why aren't turbo's fitted? As far as i can see they now are. 1.4 petrol with added bits giving the same old pulling power of 2.0, but modern economy, which makes the margins between petrol and diesel much smaller. This thread has dveloped a theme of power/economy as opposed to reliability. In my experience the disels I have owned since 1995 have been far more relaible than petrols before then. And that includes one that was 12 months old when I filled and ran it on petrol for a few miles till it conked out - carried on covering 30,000 miles with us and 30,000 for our friends who bought it from us. Current 2.2 Espace and 1.9 Megan covering 45 and 55,000 respectively. Diesel every time.
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Barneybear, Of course early to mid 90s onwards was the period where we got rid of old transistorised ignitions and carburettors, it was also the time where the old 60 or 70s engines were finally killed off by emissions regs - nearly all car factories were robotised by this point - all cars have got far more reliable. what you are experiencing is the inherent reliability of modern cars. Not the fact that you've got a diesel. Look up HJ car-by-car for any popular model - check out the problems, you get reams of failed and broken diesel related paraphernalia. the mileages you're talking about 45-55K are nothing. My petrol Jag XJ8 covered 170K trouble free miles and I used to drive that like I stole it, my petrol Audi 200 covered 164K miles at the point I sold it - fine, my XJ6 was perfect at 150K miles when I sold it, my Petrol Citroën XM covered 140K with only a clutch replacement my Xantia, Honda CRX and Primera 150K+ without! I sold my XJR at 100K miles, engine again was perfect, although the supercharger was replaced under warranty- I didn't even know there was a fault the dealer changed it during a service! I have never had an engine wear out on me despite often being a very high mileage driver. Why? I warm my cars up gently and change the oil/filter between service intervals. I do drive my cars hard occasionally - I'm no light footed taxi driver. I have to think back years to a point where I actually broke down - and that was a diesel (Pug 605 headgasket) in its defence it had done 140K miles - though that sort of mileage didn't faze any of my petrol cars.
Petrols are hampered by stupid catalytic converters and emissions laws that suit diesels. Modern petrols would be far more fuel efficient if we were allowed to go down the lean burn route, the way the emissions regs have developed we have closed off any possibility of advancing petrol engine design while we are measuring plant food as a pollutant - madness.
I like modern diesels but to suggest they are more reliable than petrols is simply not true, the engines themselves might be, but you'll never find out coz something in the fuel/emissions system will render it uneconomical to repair before you'll find out.
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Petrols are hampered by stupid catalytic converters and emissions laws that suit diesels.
How do you come to that conclusion ? EU5 & 6 are forcing diesels to get down to almost petrol NOx emissions by 2014. Currently a diesel produces 250mg/km to a petrols 80.
By the time EU6 is implemented, petrol will be allowed double the CO emissions per km over diesel while diesel will have to reduce NOx to 80mg/km to petrol 60mg/km.
Exactly how is all that stacked in diesels favour ?
Since EU3 diesel engines have also had cats fitted, they are further hampered in EU4 with an added DPF in most cases (there were some exceptions).
Modern petrols would be far more fuel efficient if we were allowed to go down the lean burn route
Totally agree with you there.
the way the emissions regs have developed we have closed off any possibility of advancing petrol engine design while we are measuring plant food as a pollutant - madness.
I don't think you can count SMOG and acid rain as plant food, not even this Government would try to claim that one. Look at LA and its air polution problems. 0 diesel cars on the roads in California.
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>Honda have shown 100+ bhp per litre -
yes if you want all your power while its screaming its nuts off.
The peak petrol power is there all right, you just have to accelerate all the way through the rev range to get it. With a diesel you dont.
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>Honda have shown 100+ bhp per litre - yes if you want all your power while its screaming its nuts off. The peak petrol power is there all right you just have to accelerate all the way through the rev range to get it. With a diesel you dont.
There are plenty of torquey petrol engines that can be rowed along on torque alone, the 2.0 litre XU PSA engine in my XM and Xantia would pull from tickover, the Lovely 150bhp engine in the UK only Civic Type S - pulls like a train at any revs, ditto the Rover VVC fitted to the Rover 25 (125 bhp variant), the Dolomite Sprint,the lovely 8V GTI VW lump - grunttastic. All perfectly torquey petrol engines that do without a turbo.
Now compare like for like, look at the Turbo Ford focus 2.5 - compare that to the diesel version fitted to Volvos, ditto for the Beemer 330s. A turbo petrol will pull from tickover and then have far more power up the rev-range. there are also lovely petrol low pressure turbos, the PSA 2.0 litre, the Rover 75 1.8T, VAG FSIs, Vauxhall's 2.0t (actually a SAAB unit) all very grunty with excellent in-gear acceleration from low revs and unlike most diesels you don't have to keep chucking gears at the thing as they're not restricted by a tiny 3,000 rpm rev band before they run out of puff. The modern sequential turbo diesels are getting better,.
Again, remove the turbo, with a modern diesel, what you are enjoying is a low powered engine made viable by a turbocharger. No such probs with a petrol which are powerful in any guise. This is the point, diesels are not great engines, turbo diesels are.
Edited by rtj70 on 18/01/2010 at 21:00
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I like the way the thread title purports to be a thread singing the praises of diesel and then the OP openly admits to disliking the things... Just another excuse to knock diesels... Sad that people who dislike diesels have to stoop so low.
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I have had two diesels, a Mondeo TDCi (130PS) and a Mazda6 (143PS) and both I have liked a lot. Before these I had some VAG 1.8T (petrol) cars so I think I've grown to like turbos full stop.
My next car will either be another turbo diesel or possibly another light pressure turbo petrol. If I could have had another VAG turbo petrol in 2003 I would have but the company scheme changed at the time to exclude VAG. They are back on the list and when I change I might be able to get an Audi A4 or A5 2.0T (180PS) for no more outlay!
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"I like the way the thread title purports to be a thread singing the praises of diesel and then the OP openly admits to disliking the things... Just another excuse to knock diesels... Sad that people who dislike diesels have to stoop so low."
Please enlighten me as to where you read that I openly admit to disliking the things. I do actually want to buy one, but can't get my head around all the problems which seem to be associated with them.
Sad that people who can't read properly sink so low :-)
Frederick
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Here:
""Back to the OP's question - my gut (as opposed to limited technical) response is that diesels of any age (subsequent to the 'old' school type that is..) are a liability waiting to happen ......"
That's exactly my feeling, rightly or wrongly.
Frederick"
If that agreement doesn't show your true feelings about diesels then nothing does... Its clear you had made up your mind before yopu even posted the OP and therefore the heading was misleading in the extreme... All cars are getting more complex, look at TSi petrols for that, its a fact of life... but what is also a fact of life is that the vast majority of diesels DO work fine and last for many miles without breaking...
TBH if we all believed the cods that some people say about modern cars and their complicated electronic and mechanical systems we wouldn't buy any modern car but go out and buy a Morris Minor... but cars from the 50s, 60s and 70s were notorious for going wrong, needing an engine rebuild every 60k miles and usually ready for the scrappy around the same time... Modern cars are a positive joy compared with them...
All you can do when buying a car is do all the checks you can and then trust that you have got a good 'un. You are just as likely to get a duff petrol as a diesel... if you are that scared of diesels, then either don't buy one, or get a decent warranty for it!
All you will get if you ask whether they are unreliable is a very limited number (in comparrison with the number sold) of sob stories from people who have an axe to grind.
Edited by b308 on 18/01/2010 at 21:28
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All you can do when buying a car is do all the checks you can and then trust that you have got a good 'un. You are just as likely to get a duff petrol as a diesel... if you are that scared of diesels then either don't buy one or get a decent warranty for it!
This is simply untrue, yes all modern cars are reliable but these diesels off the top of my head are known to have lots of problems compared to the more reliable petrols:-
BMW 3 series (up tp 2009 - too soon to tell with the new ones)
Mercedes C class (current)
Ford Mondeo III
Honda Accord (current)
Honda CRV II
Nissan Primera III
Nissan X-Trail
Jaguar X-Type
Jaguar S-Type
Volvo XC90
Most VAG powered cars (premature cambelt failure)
I'm sure people could add plenty to the list. Go back 20 years and beyond the diesels were more reliable, but then they were simpler machines then.
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I see the VAG cambelt one has appeared again... I'm now on my third and not experienced it yet... So I'm either just lucky, or its another old wives tale...
Can I see your independant statistics to prove your ascertions, SL?
Yes, if things go wrong then a modern diesel will cost more to repair than a *conventional* petrol, but I haven't seen any stats to prove that diesels are any less reliable than petrols... and as i said before, with super and turbo charged petrol engines now being built I can see the same acusations being thrown against them in due course!
Re the VAG engines, a firm of minicabs we use have Superbs on their books, 130bhp diesel ones, many of them have covered 200K plus miles without any engine problems, modern diesels can be just as relieable as older ones...
Edited by b308 on 18/01/2010 at 22:05
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There is no "VAG Cambelt Problem" - just a money grabbing scam from MK dictating a 4 year change policy which is not documented anywhere else on the planet or in the printed service data.
Some of the VAG petrol engines have used plastic FAG tensioner wheels which were of inadequate durability but every diesel I've seen has used metal wheels.
The PD engine is one of the most trouble free units made and is capable of starship mileages. The 1.9 130 PS unit is the best of the bunch.
659.
Edited by 659FBE on 18/01/2010 at 22:15
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Reliability has started to suffer due to the complications of installing a TURBO.
As both petrol and diesel take this "emissions reduction" route, and more and more power is being pumped out, due to consumer demand, more complicated fuel pumps are being used.
All these along with a never ending list of extras, fitted as standard, will inevitably lead to increased failures.
well that's what i think.
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"If that agreement doesn't show your true feelings about diesels then nothing does... "
Well you must know me better than I know myself! I don't read it like that and it's a shame that people do get so het up. But there you go.
Frederick
Edited by Frederick on 18/01/2010 at 22:35
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Again remove the turbo with a modern diesel what you are enjoying is a low powered engine made viable by a turbocharger. No such probs with a petrol which are powerful in any guise. This is the point diesels are not great engines turbo diesels are.
There are other comparisons which can be made though:
BMW 335i Touring - twin turbo, 306PS, 300NM, 0-62 (auto) 5.9s, 30.4mpg average
BMW 335d Touring - twin turbo, 286PS, 580NM, 0-62 (auto) 6.1s, 41.5mpg average
I picked the autos to make the comparison more accurate.
I agree that diesel's without turbos lack power but the current trend is towards turbocharging petrols too, my 330d pulls cleanly and linearly to 5K rpm and the torque (500NM IIRC) and gearing make the 'rev range' acceptable. I'd concede that some diesel engines (e.g. my old VAG 170PD) have a compressed rev range but then I'd not recommend that particular engine to anyone.
You can make an informed choice to drive many modern turbo diesels over their petrol counterparts (BMW 330d/335d over 330i/335i, Honda 2.2 iCTDi over 1.8 VTEC for instance) without being a mimser.
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That why I said earlier that modern sequential turbos don't suffer as badly with short rev ranges. in your example the petrol could easily make that power without a turbo! It's obviously very softly tuned then lightly blown to meet some artificial emissions category. the trend toward turbo charging petrols is to meet stupid plant food emissions targets, petrols do not need a turbo or the complexity that goes with them - diesels do. As I said before this CO2 nonsense suits diesels.
All current engine development trends are to meet a meaningless CO2 emissions target - I wouldn't mind if actual pollutants were reasons driving development. So we've constrained ourselves by artificial meaningless constraints and then build ever more complex engines to meet them! Perfect to keep big business rich, make cars overly complex requiring dealer servicing at the same time limiting the service life of a car that should last 20+ years - which would be really good for the environment...
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...in your example the petrol could easily make that power without a turbo!
I'd contend not without revving its nuts off which makes it harder to 'extract' that performance..... Doesn't the turbo (in both fuel types) increase the effective volume of the setup i.e. make it drive like a bigger capacity unit ? I think that's the point of the BMW 335i - to make a 3.0L 6 drive like a 4.0 V8 and not primarily emissions.
SWMBO has the VAG 1.4TSi 122 in her Golf and tbh it drives really nicely, like a 1.8 or even 2.0l from 5 or 10 years ago, I have no problem with turbos on either fuel type, the future (possibly even in our lifetimes) probably isn't the internal combustion engine anyhow.
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>> ...in your example the petrol could easily make that power without a turbo! I'd contend not without revving its nuts off which makes it harder to 'extract' that performance..... Doesn't the turbo (in both fuel types) increase the effective volume of the setup
>>
A modern 3 litre petrol engine with variable valve timing would have plenty of torque available without a turbo, not as much as the blown car but easily enough! Yes a turbo gives you the power of a larger engine, how often will you actually be using anything like all that power? It was fun to boot my supercharged Jag XJR off the lights (370bhp + silly amounts of torque) but in reality most of the time I'd potter about like everyone else. the normally aspirated revier XJ8 I replaced it with was every bit as fast in the real world unless I wanted to go chasing Porsches and being a big engine it was plenty fast enough to make good progress on a whiff of throttle - surprisingly economical too, 30mpg cruising on the motorway.
I borrowed a 330d, the engine was fabulous, (shame about the ride quality) however flicking to the trip's mpg figure when I first borrowed the the car showed an average of 23 mpg, I soon had it up to 27 (the owner had a lead foot) it just shows any car will drink fuel when thrashed. I only did about 300 miles in the car so I couldn't get a proper feel for fuel consumption - my gut feeling was it was nowhere near the above figures unless you drove like a nun.
We only worry about fuel cost so much because we're taxed so much!
Edited by SteveLee on 19/01/2010 at 00:27
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I borrowed a 330d the engine was fabulous (shame about the ride quality) however flicking to the trip's mpg figure when I first borrowed the the car showed an average of 23 mpg I soon had it up to 27 (the owner had a lead foot) it just shows any car will drink fuel when thrashed. We only worry about fuel cost so much because we're taxed so much!
I don't think I drive like a nun yet I easily get more than 40mpg (actually 44-47mpg), mine's (by choice) a manual and I'd admit that most of my mileage is 'highway' as the Americans would say, I (again deliberately) heeded the road tester's advice (most don't) and got the SE spec, it rides reasonable well on 17" wheels and runflats imho - about on a par with an Audi A4 S-line I'd say. It was OK in the snow too.
I think that there are just 'good and bad' engine designs, my previous VAG 2.0 170PD (so not the much loved 1.9) was thirsty, unrefined and had a usable rev range of no more than 2000rpm so was a pretty bad example of a diesel I'd opine, however the latest 3.0d from BMW is a good example of an engine 'full stop'.
Same goes for petrols, the VAG 2.0 115PS in SWMBOs Golf IV 10 years ago drank oil and was neither powerful for its displacement or particularly economical, first impressions of the current VAG TSi are that it is both powerful and refined, I certainly wouldn't base my opinion of petrol engines on the old VAG 2.0.
Finally as for fuel tax, if fuel wasn't taxed then something else would be, there's a strong argument that taxing the amount of a scarce resource we use is fair, as for where the resultant revenues are spent - that's a different issue but applies to all forms of taxation doesn't it e.g. I don't like the fact I've subsided the glut of little Hyundais and Kias which have suddenly appeared on the roads.
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e.g. I don't like the fact I've subsided
Meant to type subsidised, spellcheckers....
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A modern 3 litre petrol engine with variable valve timing would have plenty of torque available without a turbo not as much as the blown car but easily enough!
If this is true why aren't HGV manufacturers copying the Lexus trick taking a big V8+ petrol engine (tuning it for torque), putting a battery pack in the cab, it doesn't have to actually power the vehicle as we have seen, and calling it a hybrid.
It would save millions in city centre congestion charge tax.
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It's only the latest direct injection petrol turbos that give the turbodiesel wallop without low 20's mpg figures.
The beauty of a good turbodiesel is that you can have 300+NM of torque to sling you up the road, or 50 mpg if you want to be sensible. Only the very latest generation of petrol engines get close. The 2.5 Volvo / Focus engine is notoriously thirsty when used to anything like its potential.
And let's face it most acceleration on real roads is in bursts rather than standing start drag race type stuff. Coming off a roundabout, joining a motorway / dual carriageway. stuff like that.
My PD VW (like many other turbodiesels) will squeeze me into the seat from below 40 mph and not need another gear change until comfortably beyond the legal limit. Only the irritatingly short first gear ever causes me problems with regard to gear swapping.
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Hmmm
dodgy VAG timing belts
Never heard of them
Re timing belt failures in general, I think human nature plays a big part
First forget / omit to replace, then sell the car and lie to the effect it was changed.
Net result : failure and blame the belt. simple.
Plus the tensioner issues, across the various marques
I repeat
VAG 1.9 TDI, 210,000 miles
( and been taken to 300,000 plus in local Audi "without spanners")
Still with the Origional head gasket,
NO belt failures, crankcase oil seal leak is all
Still on the origional pump & injectors
origional turbo too
I have however changed the oil occassionally ( smiley def required)
Started at -12 recently ( a bit reluctantly I admit)
So whilst there are some wonderful high performance high revving petrols out there
for the general business of getting from A to B, moderate to high milage
Its gotta be diesel ( & turbo)
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Nail on head, DD... its all about proper upkeep, if the previous owner looked after their car then it has a better chance of being ok, if not then you're more likely to get a duffer regardless of the fuel used.
Frederick, I read your posts and, to me, that post I quoted seemed to be very clear that you had already made your mind up before starting the thread, if thats not the case, and you are truly open to change to diesel, then I appologise... Its just that I've seen too many threads which (like this one at one point) end up as a diesel-bashing one and tbh I tend to get a little fed up with it... especially as most cars these days are the ultimate in reliable machines considering what we put them through... and especially compared with what we used to have...
If you use the search function you will find plenty of previous threads discussing the reliability, or otherwise, of the modern diesel, and in the process giving you a list of things to look for and questions to ask when buying one, I'd suggest you try them, this thread has so far just been another repeat performance!
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Well, this thread has certainly turned out to be an eye opener and has resulted in me biting the bullet :-)
b308 - are you ready for this?!
I HAVE TODAY BOUGHT AN 09 2.0 Turbo Diesel
Not going to mention the make in case someone starts giving me the jitters as to how crap it is :-)
All the best lads,
Frederick
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b308 - are you ready for this?! I HAVE TODAY BOUGHT AN 09 2.0 Turbo Diesel
:-)
I can only hope it goes ok or I will be hung drawn and quartered!
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I would have a petrol turbo every time over a diesel turbo, having had both.
The turbo petrol 1.8T i had gave maximum torque from 1950 rpm up to 4500 rpm. That wide torque band gave a very relaxed drive.
The engine was silky smooth and quite, the only reason i don't drive petrol today is the VED and fuel costs.
The latest xtrail diesel i have peaked at 2000 rpm, after that torque drops off, taking it over 3500rpm is pretty pointless, while a petrol will still put out good torque at 5000rpm.
Anyone who claims the diesel is the best choice is doing so on a cost basis.
Which is why i drive one, band J, and 40mpg, from a 171bhp 266 pound feet torque, does it for me, not as fast as the petrol, just cheaper to run, and easier to sell on, and keep good residuals, as i said it all about costs.
Money no object, turbo petrol every time.
And by the way the xtrail is a chain cam.
Edited by xtrailman on 19/01/2010 at 10:04
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Anyone who claims the diesel is the best choice is doing so on a cost basis.
No they aren't! I can have any engine I like in our motability car, I chose diesel because I prefer the way it delivers the power, the economy is a handy side effect, not the be-all and end-all!
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I chose diesel because I prefer the way it delivers the power
I would have agreed with that once, but now I've experienced what a proper V6 petrol can do, diesel doesn't come close. My car revs freely up to 7000 rpm and picks up very comfortably from as low as 1200rpm. It's like having the urge of a turbo diesel, with a much wider power band and a gorgeous growl to go with it.
I do agree that a 4 pot diesel is far better than most 4 pot naturally aspirated petrol engines, thinking in terms of their power delivery.
I've driven some very good diesel engines and liked them at the time, but I have to say I'm really enjoying driving a gutsy petrol at the minute.
Plus, I get heat through the vents very quickly, unlike most diesels. Much to be said for that at this time of year!
the economy is a handy side effect not the be-all and end-all!
I'll admit my fuel economy isn't so great. Fortunately, it isn't the be-all and end-all, as you say...
I might go back to diesel again one day, but I'm not expecting that it might somehow be better than a proper 6+ cylinder petrol engine, or even a turbo charged 4 pot petrol, unless fuel economy is what I'm after at the time.
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Horses for courses I think. I drive ordinary cars in ordinary circumsatances, run diesels for the last 17yrs and in no rush to go back to a petrol. Not interested in out and out performance, but it's nice to have enough grunt to overtake and to cruise fully laden without undue strain. It's not the width of the torque band in revs that matters but the time taken to traverse it in ordinary driving. Slower revving and higher gearing in a diesel mean you're nit actually stirring the gearbox any more than in an equivalently priced/specified petrol.
Hired a 1.6 Scenic in December. At idle it was far quieter than the family 1.9DW3 Berlingo. Actually out on the road it was quite raucous and much less willing and flexible when climbing Scottish mountain passes.
Also it drank fuel and I stalled it more times in a day then I've stalled diesels in nigh on two decades!!
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> >run diesels for the last 17yrs and in no rush to go back to a petrol. Not interestedin out and out performance but it's nice to have enough grunt to overtake and to cruise fully laden without undue strain. It's not the width of the torque band in revs that matters but the time taken to traverse it in ordinary driving. Slower revving and higher gearing in a diesel mean you're nit actually stirring the gearbox any more than in an equivalently priced/specified petrol.
That's it. And with a bit of care 60mpg is possible, made easier if the driver's seat is very comfortable with your favourite tracks playing on the iPod.
bigjohnd.org.uk/C4/OtherPhotos/60mpg.jpg
(53-55 is more like it in 2010)
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>Anyone who claims the diesel is the best choice is doing so on a cost basis.
I agree absolutely. Diesel has only one advantage and that is fuel efficiency.
The folks who claim that they prefer the torque/power-characteristics of modern diesels forget that a normally aspirated V8 petrol can provide superior driveability without the expense of DMFs, DPFs, fancy injectors and fuel pumps.
Kevin...
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Hi,
Glad someone else appreciated the Maestro/Montego economy. Long ago, I had a Montego, admittedly not A series powered, but, 1600 cc reasonable handling, with economy. Brim to brim, not guessing, but calculating accurately, 38mpg over a 400 mile fast (90mph a lot of the time not in UK obviously) trip was good economy on an SU HIF carb, and it probably had more potential. Now, fuel economy's marginally better, but cost of servicing/repairs? The complexity of my LPG converted Vectra was beyond the techs at the main dealer, so what hope has the backstreet garage/diy man? Save £200 a year on fuel, pay £1002 for a repair that took 3 months to do! Economical? No way!! Cats were foisted upon us for the benefit of the precious metal manufacturers, not the environment, IMHO! Maestro/Montego electronics were rubbish, though!
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re: characteristics, I've been doing the commute in the Golf, and today switched back to the Volvo. Forgetting the car itself and commenting purely on engines / performance, the Golf is the quicker car in the real world.
Some examples:
Exiting 50 mph/SPECS stretch. Getting the Volvo from 50-80 mph anywhere near as quickly as the Golf would involve a gear change or two. The Golf will push you into the seat in 5th from 50 mph and pull up past a ton if you want it to.
Rush hour motorway (40 mph ish) in lane 1, spot a gap in lane 2. Leave it in 4th, squeeze the throttle. The trick in the Golf is not hitting the car you've pulled out behind up the chuff. The Volvo will do it, but you are aware you'll be going a lot quicker in 3rd.
Joining the A316 on my way home, the slip road is a fairly short, very steep uphill coming off a tight (30 mph) roundabout. Exiting the roundabout in 3rd, the Golf can be doing 70 mph at the top of the slip without ever exceeding 2500 RPM. The Volvo, even using 4000 RPM will just about manage 60. To match the Golf's speed, you need to join the slip in 2nd, and use the revs. Driven like this, the Volvo does 26 mpg. Kept under 2500 RPM, the Golf is doing 53 on the commute, and losing nothing in terms of speed.
The VW PD sounds and feels truly horrible compared to the super-smooth Volvo 5 pot turbo, but the delivery is fantastic for the road. Loads of grunt, right where you need it, and you can make ridiculous progress using barely more than half the available revs on offer. Its biggest limitation is first which is over soooo quickly, and in which the torque overcomes the available traction with almost comical ease. It will also blink the traction light / spin the wheels in 2nd if there's so much as a hint of damp on the road. The Volvo's delivery is much more linear, the traction off the line far superior, and of course, extends 2000 RPM higher.
The fact is the diesel offers the same or greater speed (keeping within limits-ish), for less effort and half the fuel consumption. On a track or a B-road blast where you can really enjoy yourself, it's petrol every time. In the cut and thrust of a rush hour commute, give me diesel any day.
Just a shame the Golf itself isn't anything like as nice a car as the Volvo. But hey. :-)
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DP, what you say is true if you want to leave the car in the gear it's in, however put an autobox on both cars and the results might be very different.
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Actually I would contend the modern multi speed auto box ( or automated manuals such as the DSG ) work in FAVOUR of the diesel.
With their narrower range of "optimum efficency" / engine revs.
But then on the other hand the stupendous torque of the diesel means one can pull much higher gearing, so a greater speed variation is available within a limited rev range.
Gibber & mumble & twitch
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But then on the other hand the stupendous torque of the diesel means one can pull much higher gearing so a greater speed variation is available within a limited rev range.
Exactly. People who complain about diesels "running out of revs" are not driving them properly.
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I'm not really into diesels, and never have been really, I had a Pug 306 TD which quite impressed me I must say (Turbo, see!)
I also had a rather nice Discovery XT auto which was a gem.
Ere!!! I've had a few diesels after all :) but the best diesel I owned was a nice little AX 1.4 with the all aluminum 1360 TUD engine, it took us to Tenerife and back (via Portugal) and never missed a beat, until I decided to change the fuel filter and got air in the system.
I've always been of the school of "sounds like a taxi" merchants but - that little 1360 injun sounded like a petrol, hot or cold, and boy was it eco-nomical.
If mini and micro cars are fitted with all this DPF, CR stuff, then its a retrograde step IMO.
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>>Maestro/Montego electronics were rubbish though!
I had a Montego 2.0 Turbo (petrol). No laughing at the back! It was an old fashioned turbocharged engine, but very rapid when it was on boil. They had a Garret T3 turbo which is a fair size, so after the turbo lag, there would just be this relentless push like a big hand behind you. Nothing like as smooth as todays petrol turbos, but very exhilarating. Mine was modified, and managed to put the power down with hardly any torque steer, as it was a later one, which had the engines lowered to straighten the driveshafts.
Surprisingly fast at drag strips due to this fact, but you're right, the electronics were Lucas which were hopeless. I had to change the ignition advance unit twice on mine to get it back on the road.
Crude but great fun....
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The Montego Turbos were seriously quick. A friend had an early one (C plate) which scared the hell out of all of us before he had a modified carb needle and wastegate fitted. Dyno'd at 202 bhp when it was finished, and would smoke the tyres on full throttle, in the bone dry, in the first three gears! Used to tug the steering wheel out of your hands on hard acceleration, and would break the occasional driveshaft, but we got good at changing them. :-) An animal of a car, and amazingly reliable, especially given the relentless, daily abuse he gave it. I don't think this car was ever driven sensibly.
Edited by Webmaster on 20/01/2010 at 02:00
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An animal of a car, and amazingly reliable
Mine was lowered an inch and black, so it looked mean. A friend of mine had one that was highly modified as his second car, and you got tunnel vision accelerating on full boost!
The engine was actually extremely strong on them. It was a modified O series with sodium cooled exhaust valves and a very tough bottom end.I never had any problems with mine apart from mentioned electrics.
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Very much agree about the greenies and the cat. If lean burn or stratified charge technology had been developed our engines would be putting out less pollution because they would be burning less fuel in the first place.
There was another story told about the cat, the Euro emmision standards wre said to have been set in such a way so that the only way to meet then was to use a platinum based cat. An EU politician was supposed to have a big corner of the world platinum supplies at the time. Don't know if there is any truth in it but a nice story.
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I like diesels. I like modern diesels.
I like modern diesels from manufacturers with a good track record in making them..
So I will not buy Mercedes - built in injector issues, (even if I wanted to afford them).. or Mazda of GM (GM engineering is pants imo)..or Renault..
I buy a diesle engined car with proven reliability.. 2-3 years experience in real life so proven reliability and lots of second hand working spares from crashed ones if and when I need them.
Nothing with hugely complex systems the dealers know nothing of...
And nothing from makers whose dealers are pants (Renault again)..
And do some basic research on failures before I buy..
So far my Yaris diesel has been fault free (touch wood) engine wise: ditto our Peugeot 106..
I would buy a Ford one: but not SAAB..
As for Renault.. anyone who buys a Renault diesel with their own money !!!
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As for Renault.. anyone who buys a Renault diesel with their own money !!!
Post 2003/4 Renault diesels are fine, and wipe the floor with any of their contemporaries for refinement and smoothness.
The inherent issues with the 1.9dCi engine were well known, acknowledged by Renault, fixed permanently, and warranties extended for affected owners (with service history). I wouldn't say you're any worse off with a Renault dCi than a Ford TDCi or even a BMW diesel given the reported issues with those. It's only the bad ones which get the press, and Renault are the only ones I can think of who ended up sticking their hands up and doing something about it.
Renault cars have their issues, and plenty of them, but the diesel engines are fabulous. Ours never skipped a beat, even though the rest of the car started falling apart around it.
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Lots of interesting views in here and I'm in the Golf 2 Litre Turbo Diesel camp but I have to admit that petrol engines are catching up on the torque front - witness the Golf GTi with well over 200 lb ft (or is it ft lb?) at low revs and then loads of power to play with. Focus ST pulls off a similar trick. It only leaves the question of economy on the petrol front versus reliability on the Diesels, surely?
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I like modern diesels from manufacturers with a good track record in making them.. So I will not buy Mercedes - built in injector issues (even if I wanted to afford them).. or Mazda of GM (GM engineering is pants imo)..or Renault..
er.....weren't Mazda owned by Ford until recently (rather than GM)?
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I reckon diesels' days are numbered. Why? Fuel costs and mpg. We all got excited 10-15 years ago when we realised we could buy an "exotic" turbodiesel version of an everyday car, just like we seen on the Continent, because a) the fuel was cheaper per litre than petrol, and b) we got a lot more mpg.
Now neither of the above factors really apply any more...
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I reckon diesels' days are numbered.
If some of the power and economy figures for the new direct injection petrols are even remotely accurate, I would agree with you.
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I reckon diesels' days are numbered.
Actually I suspect the internal combustion engine's days are numbered, peak oil and all that....
Whilst I admit to generally liking diesels (especially my 330d) one thing which is anathema to me is a diesel convertible, it just doesn't seem right to me even with a superb (imho) engine like the BMW 3.0d and especially with unrefined lumps like VAG 2.0PDs in A4 B7 and earlier EOSs. The pursuit of low BIK gone mad (nearly as crazy as a V70 with a 1.6D too whilst I'm on my hobby horse).
Vented....
Edited by idle_chatterer on 20/01/2010 at 09:46
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>>The pursuit of low BIK gone mad (nearlyas crazy as a V70 with a 1.6D too whilst I'm on my hobby horse).
I agree. And especially when you consider the BIK goalposts move every few years to catch the people who have chosen low tax options, and started costing the government money. We already saw the "diesel surcharge" introduced when people migrated diesel-wards to save a few quid.
There have been many half baked company car BIK rules that have been cooked up and then abandoned over the years once people take advantage of them (list price based banding, capacity based banding, CO2 based banding). I can't wait to see what they come up with as the new goalposts when everyone's driving sub 130g/km company cars, and the treasury needs the money.
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Many breakdowns are caused by the electrical ignition systems of petrol engines - I believe the AA and RAC always name 'electrical problems' as the most common reason for call outs.
These problems can be cheap to fix, often requiring no more than a jump start.
Diesels do not have spark plugs, HT leads, etc, which tends to make them more reliable.
Where some diesels seem to fall down is on breakdowns that cost a lot to fix - DMFs.
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You can't seem to get the lovely exhaust note from a diesel. I wonder why?
The three exceptions I've heard are a DUKW on Hunstanton beach, a local refuse lorry and an old LDV twelve seater mini-bus it was my unfortunate experience to drive, all had a brief resonant frequency.
Edited by bathtub tom {p} on 20/01/2010 at 11:28
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You can't seem to get the lovely exhaust note from a diesel. I wonder why?
You will laugh at this, but my old mk2 Mondeo TD, which sounded truly awful in almost every situation, had a nice rasp from the tailpipe at idle. It was completely drowned out by the din of the engine in daily driving, but stood behind the car at tickover, it actually sounded quite nice.
I wonder if the generic thing with exhaust notes and diesels is to do with the presence of the turbocharger, as many turbo petrol engines suffer from the same thing. This is a guess by the way. :-)
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Diesels are certainly much better at waking your neighbours up at 6am when you start them and leave them chugging away for 15 minutes before driving off, which our neighbour does regularly.
(It's a newish VAG turbodiesel, but it still sounds like a bag of spanners when started on a cold morning).
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pyruse, so where is the problem in that ?
Some of my neighbours are students and they keep me awake in the early hours (since their body clock's are constantly on social weekenders - hence have no concept of getting up early for work) so I have no problems with starting a very noisy clatter box in the morning !
The colder weather the better I say.
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You can't seem to get a lovely exhaust note from a diesel. I wonder why?
What about this one?
www.youtube.com/watch?v=V7H1rdHXs8Y
Listen to the revs of the car he passes compared to his car. Surreal.
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Where some diesels seem to fall down is on breakdowns that cost a lot to fix - DMFs.
Yes, I think thats true, although DMF seldom causes an actual failure to proceed.
Most common cause for all cars (probably 25%) is battery trouble, this applies to petrol and diesel.
HT system used to give us problem on petrol cars (coil failure) but I think for the last four years things have improved a lot and we dont get many at all now, I think coil quality has improved a lot.
Other failures tend to relate to sensors, burst hoses and random electrical problems.
I think diesel and petrol have similar reliability but diesel faults are much more costly to fix. A lot of independents operate with a higher labour rate for diesel repairs, this is due to cost recovery for the investment in diagnostic kit and higher level of diagnostic skill required.
On a petrol once you have got the DTC (code) then the fix is usually straightforward, not so with diesels which often seem to defy logical fault finding.
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WT - what is your view (if any) on direct injection petrol engines? You must be seeing some of these with a few miles on the clock nowadays.
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WT - what is your view (if any) on direct injection petrol engines? You must be seeing some of these with a few miles on the clock nowadays.
So far the omens are good. The fuel system is still a lot simpler than on a CR diesel. The only common problem weve had (and its only on a few cars) is wear of the HP fuel pump follower on the VAG cars. However these are quite cheap and easy to replace and probably worth replacing (or at least inspecting) every 30k. We have heard of cams also been damaged on the earlier engines, though not seen any, and apparently the cams have been made harder.
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I was in the pub last night with a colleague who'd been seduced into leasing an A3 Cabriolet with the 1.9PD engine with DPF.
Unprompted by me they were bemoaning the dreadful tractor like noise of this engine, its constant and smelly DPF regeneration and had taken the issue up with both Audi and the leasing company as they didn't feel they could live with the car and that this engine was unsuitable for a convertible. I suspect they'll get little or no luck but it highlights my point about the awfulness of VAG PD engines in convertibles, BIK avoidance gone mad......
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I've often wondered what's the point of chopping the roof off a car that sounds like a London taxi.
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Then again, I like to hear the turbo whistle and the waste gate.
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