Having read the many post on the tales & woes of diesel I can understand how some are disilutioned. I do however wonder how many people have made the transition from petrol to diesel without any real understanding or knoledge of a diesel engine. I have run loads of CRI vehicles including the infamous 2.0tdci to very high milage without any problems at all. I have never had a turbo or head or injector or EGR valev & have nothing but praise for the reliability. However I double my oil changes from new with carefull running in for 3000 miles with a very gradual increase in revs, when starting from cold I allow to tick over for 30 seconds before I move & I drive gently without turbo boost untill the temp gauge is out the blue, I don't change down to overtake I use the torque very rarely going over 2500 rpm, mostly 1600-2250, I always use a major brand of fuel ( & not supermarket ) I use fuel line cleaner every 3000 miles ,Always allow the engine a slowing down period after a hard run & allow to idle for at least minute before I switch off. I cover huge milage & tow a 1500 kg caravan all over europe for the last 12 years with no problem on reliabilty!.
I have however had clients take me out in there diesels under what they would call normal driving & cringe at what they do to an engine! do they understand that diesel components are so much heavier in an engine that the stresses are much higher
I wonder If any research has been carried out into this
Regards Doc
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So your advice would be that buying a new one would be OK, but a 2nd hand one would be a bit of a gamble?
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In general I agree, I have not gone to the lengths of injection cleaner or halving oil change intervals (mine is done every 10k ish (recomended 12.5k) however using the torque and not the revs makes sense, exceeding 3000 revs is rare.
I have been with people in a diesel who have sat in say 3rd behind a slower vehicle at around 3500 revs, floored it when clear and hit the limiter while overtaking, driving it like an n/a petrol car, when a higher gear using the torque would be quicker, safer and more relaxed.
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So lets get this right. You drive it very gently, you treat it with kid gloves & it's reliable..... So would anything else be. Living in the real world & having done 11,000 miles in 5 months in the Jag & did 61K in 24 months in the Alfa, I drive them like I need to get somewhere. I don't cane cold engines diesel or petrol & I do allow a simmer period before I switch off. But the rev counter sees the near the red line as required, the very poor low down torque means in a manual you frequently in the wrong gear (jag is auto) & the top end is rev limited, again not an issue in the auto.
Personally the Alfa cost me a fortune with the various bits of Bosch common rail dying & the Jaguar if it wasn't under Jag warranty would give me sleepless nights, twin VNT turbo, 4 cams, 2 cam belts, 2 cam chains etc etc.
I only run a diesel because of the stupid VED in the UK, otherwise it would have been a simple & reliable 3.0 litre petrol returning not too dissimilar fuel figures.
I'd suggest you've been very very lucky!
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>>So lets get this right. You drive it very gently, you treat it with kid gloves & it's reliable>>
Allowing say a 2.0 TD to produce 250lb/ft at under 2000 rpm is not treating it with kid gloves, a lot of boost pressure is involved, turbo spinning at 10's of 000's or rpm etc, the point is using the characteristics of the engine to best effect.
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>I have been with people in a diesel who have sat in say 3rd behind a slower vehicle at around 3500 revs...
I think that would be about 65 mph in my diesel - truly bizarre driving behind any kind of engine!
Incidentally, where does all this sit with the advice of HJ and others to give a diesel a good revving once in a while to keep the top of the engine clean? It's with this in mind that I tend to take mine up to cruising speed in third - away from a ring-road roundabout, say - and then change straight to fifth. (The D5 sounds rather nice treated like this, and it's had first-time smoke passes at both MoTs so far!) According to ID's method, should I be gently easing it up through the gears in the way that OldHand so despises? }:---)
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I applaud and agree with your methods of running/running in. My belief is that diesels not worked hard are the ones that give the troubles. However oil changes arent realy the issue with CR reliability. I think the issues are sensors, or the ability to cheaply build a reliable 1200+ Bar diesel pump.
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so if I believe OP's case, all the 100k + miles PSA HDI units have been driven gently on motorways?
Cow excrement is a phrase that comes to mind.
madf
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CR Diesels are not failing (mostly) through lack of oil changes or because a cam has snapped or a con rod come through the block. Its mostly problems associated with the fuel system and the other bits and pieces like DMF. Careful maintenance and driving can't do a lot to prevent most of these problems.
With all due respect to posters in the BR, their comments on reliability are not really valid because the sample is so small. The number of motorists who post in the BR is almost an infinitely small percentage of the c.26 million motorists in the UK, so you can't get any feel for the significance of the information.
For example, most BR's would say they have not had a clutch wear out in the last 5 years - yet I know a guy who runs a clutch replacement centre and all he does, all day, every day, is replace clutches. Similarly I know another guy who has run an automatic transmission repair business for over 30 years (now taken over by his son) and all he does is repair auto transmissions day-in day-out - which most people will say are very reliable. You really need to see the big picture.
My friend who has gone into business (or rather changed the direction of his business) to specialise in Diesels has done so becasue there is a shortage of expertise and experience and he can charge a much higher labour rate (as an independent) than if he were still doing general repairs and petrol injection diagnostics, where the repair market is much more competitive.
He almost always has a full book for 1-2 weeks ahead, and the jobs tend to be much bigger and more expensive than fixing petrol injection faults. As he says, when he was doing general repairs customers would ring up and ask ' how much to fix it?'. They now ring up and ask, 'CAN you fix it?' - usually having already shelled out £100's at a main dealer and still having the problem.
There are also some nice peripheral repairs on Diesels. He does quite a few turbo changes and also starter motor replacements on the Ford TDCI's. On the Fords, the DMF's can start to fail quite early, as they wear they throw off swarf from the DMF mechanism, this bungs up the starter motor leading to bad starting. So he replaces the starter and then a few months later the vehicle comes back with a failed DMF and so that's another job to take a profit on.
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Oil changes do help with the relibility of the EGR valve as aromatic hydrocarbons are reduced with high quality oil & frequent changes reduce the sticky carbon deposits. I do give a diesel a blow out on the motorway and do drive them hard especially when towing but do not thrash them. Although I tow a 1500kg van sometimes well inexcess of 6000 miles a year plus covering 60,000 year running some tdci's up to 180000 I have never had a dual mass flywheel failure or starter failure iether & wonder whether the life of the DMF is shortened by jack rabbit starts & wheel spinning of which I do niether.
I too have spent thirty + years in the motor trade & see the full range of problems with all makes of cars & dont think one particlar make is any better than any other. I agree I see huge amount of auto box failures mostly front wheel drive & expensive they are too!.However I do belive if you have a good understanding of mechanical knowledge you can reduce the problems. The injection problem on the notorious 2.0tdci was exagerated by pump failure causing fragments in the injector system caused by insuffiecnt bedding in of diesel pump components as stated by auto data, I think thats where carefull milage at the start of life gave improved reliability.
I do not potter & my 122.9 mile commute to work each way is normally covered in under 2 hours but I just dont cane the seven bells out of them as they are my own cars.
I have had one injector need recoding but whilst it never brought the light on all that was noticable was a light misfire at 1250 & 1750 rpm when cold!.
My wife also runs a diesel & niether have iether experienced any drama & I wouldn't switch to petrol as i enjoy the more relaxed tourqey drive.
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I too have spent thirty + years in the motor trade & see the full range of problems with all makes of cars & dont think one particlar make is any better than any other.
I'm extremely surprised that you could have 30 years in the trade and make that statement!
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Aprilla, at the end of the day they all go wrong, some more than others but the ones you would expect to be top notch can be the worst offenders. the statment was a generalisation & not refeering just to diesels. with the exception of japaneese I don't think any particular make stands out a mile from the rest for reliability.
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with the exception of japaneese I don't think any particular make stands out a mile from the rest for reliability.
So do the Japanese "stand out a mile" or not then?
I don't think it's any great secret that Vaux/Ford/VW are no better or worse than Pug/Fiat these days!!!
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With all due respect to posters in the BR their comments on reliability are not really valid because the sample is so small.
Yes, its worth remembering that forums such as this are about discussing 'problems' rather than writing in to tell people how problem free everything is ! So you can get sucked into a belief that all you are ever haering about is the problems, but the silent majority with no problems are just that.
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the silent majority with no problems are just that.
I agree completely.
If you work for a company with a big fleet, a friendly chat with the fleet manager can be hugely educational as well. It's played a big part in why I've never been persuaded to shell out for a VW, it's how I know that Mercedes and Audi go just as wrong just as often as anything else, and it's how I know that 120,000 trouble free miles from a modern CR diesel engine is the norm rather than the exception, whether dCi, JTD, TDCI or HDi
But I also learned another important thing. Heaven help you if they do break!!
Cheers
DP
--
04 Grand Scenic 1.9 dCi Dynamique
00 Mondeo 1.8TD LX
97 Ford Fiesta 1.4 16v Chicane (for sale)
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Re the silent majority, this is a point I have tried to make before and perhaps failed. There might be more TDCi issue reported on here than, for instance, Honda diesel issues however the TDCI silent majority with no problems is ever so much larger.
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thank you DP & Cheddar I agree, I also have a family relative heavily involved in a major fleet of vehicles & the recall list is endless these days and the maintenance horrendous.
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for instance Hondadiesel issues however the TDCI silent majority with no problems is ever so much larger.
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Honda diesels arent entirely trouble free, but there are relatively few around compared to the Ford and VaG diesel population. Now I'm not trying to say theyr'e bad, but I have read on other boards that these engines for instance often have fuel consumption issues despite them being so state of the art.
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Always amazes me how everyone on the BR is an "expert" and dispenses their advice like it's gospel!
Only yesterday I was reading one poster that said the secret to a trouble free CR diesel is thrashing it regularly.
Now today here's someone else claiming the secret is driving it gently.
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"Only yesterday I was reading one poster that said the secret to a trouble free CR diesel is thrashing it regularly.
Now today here's someone else claiming the secret is driving it gently."
It isn't black and white - most things aren't. At the risk of sounding Blairite, there is a 'third way' - driving a car sympathetically, which doesn't mean pussyfooting around but equally it doesn't mean thrashing it. I am no mechanic but I think experience teaches one car sympathy and one can soon learn, if there is a will to, to drive briskly yet smoothly - the way the machinery is designed to perform. This way you should find that cars are reliable.
Without wishing to sound smug, I did over 500,000 miles in 7 Renaults between 1980 and 2001, then about 100,000 since then in three equally reliable German cars (VW, Audi and (so far) Mercedes).
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Always amazes me how everyone on the BR is an "expert"
Especially when we are talking about things like CR fuel pumps, which pump the same amount of fuel, to the same pressure whatever load you apply from the throttle. All that happens at high load is a little more fuel is injected, and a little less is returned to the tank. There's nothing a car owner/driver can do to bed the fuel pump in! If the fuel pump doesn't bed in, it's either a design problem, a material quality problem, or a part tolerance problem - it certainly isn't the fault of the driver!
Number_Cruncher
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