My Audi A4 has done 142,000 trouble free miles now and before that my Rover 75 CDT did 225,000 miles before fuel pump problems made me get rid of it. Would I buy a common-rail? I dont think I will, nor will I get the 2.0 PD engine as the fuel economy is 10mpg less that what I get now due to particulate filters - what a stupid idea by the EU - reducing fuel consumption when everyone you listen to is harping on about economy and how much damage we are doing to the environment.
Currently diesel shopping to replace our Rover 200 and after some lengthy trips around dealers we are going to get a late MG ZR as it has a proven reliable diesel engine, that ok isnt that refined but will travel to the moon and back probably several times and has no inherint problems. A 207/Fiesta etc is probably a better car but as this is a long term purchase, I dont think its worth the risk.
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I dont think its worth the risk.
OK understood, but as I have questioned on my similar thread, what exactly is the risk? 1%, 50%, 80% ??? All we know for sure is that some people have had problems and some of them have mentioned them publicly. Based on my own experience I would have no hesitation at all in buying another CR diesel. Ford TDCis in particular. Best cars I have ever had for reliability. We need the numbers.
Edited by shoespy on 29/04/2008 at 12:50
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Interesting thread...the overriding message is that whilst manufacturers have developed diesels to compare with petrol performance and refinement, reliability has suffered as a result. Some engines have definitely performed worse than others. The PSA 2.2dCI of the Laguna, X-Trail and others seems to be particularly troublesome.
Interestingly, the best pre-CR diesels, such as the Merc E606 3-litre diesel (normally aspirated), command premium used prices if in good condition. A good E-class diesel estate can get £6K on the private market, even with 170K on the clock. It's only 134bhp but will trundle on forever, and give around 35mpg.
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such as the Merc E606 3-litre diesel
Yes, they are quite popular. I'm biased though!
However, there is an emerging problem with them that tends to go un-noticed, and mainly unrepaired. The inlet valves and inlet valve seats are subject to recession. For a long time, this is tolerated by the adjustment provided by the hydraulic tappets. However, once the wear progresses further than can be accomodated by the hydraulic follower, compression loss follows. This produces poor cold starting, and rough running once the after-glow cycle ends.
I say that the problem is emerging because it's only now that these engines have been running for 10 years or so that the wear has progressed to the stage where the travel in the hydraulic tappets has been used up.
Most aren't aware of the problem, and blame it on fuel leaks - the low pressure fuel pipework on these engines does frequently leak. Those who do go on to either carry out compression tests, or to run the engines without the inlet manifold in place will often find this problem. Only a few of those who find the problem will bite the bullet, and go on to have the head off to fix the problem properly.
So, if you are looking at an OM606 powered MB, I would definitely make sure you listen to it start from cold, and make sure it runs smoothly all the time - in the UK climate, there should be no period of rough running at all.
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The PSA 2.2dCI of the Laguna X-Trail and others seems to be particularly troublesome.
I may be wrong, but I thought the Laguna had a Renault engine, the 2.2 X Trail was a Nissan engine, and neither had any connection with PSA?!
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reliability has suffered as a result.
Just a minor pont, but where are the stats to prove this?
As a %ge of the total number of diesel engined cars is the failure rate as bad as people on forums say it is, or are we talking a few disgruntled drivers and some others with an axe to grind?
As has been said before the people who tend to do the highest mileages, taxi/mincab drivers, tend to use diesels, and I've seen all sorts used for this trade... that doesn't corralate with the above!
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>> reliability has suffered as a result. Just a minor pont but where are the stats to prove this? As a %ge of the total number of diesel engined cars is the failure rate as bad as people on forums say it is or are we talking a few disgruntled drivers and some others with an axe to grind? As has been said before the people who tend to do the highest mileages taxi/mincab drivers tend to use diesels and I've seen all sorts used for this trade... that doesn't corralate with the above!
Yeah, as with every corroborated fault in recent times, actual quantified failure rates are hard to come by. No one could argue that the Austin Allegro wasn't a spectacularly unreliable car with many, many inherent faults but it's all words, not figures.
HJ withdrew his recommendation for the X-Trail mk1 diesel, due to the high amount of customer woe messages he received.
It's not unreasonable to say that the long-held 'longevity' quality of a diesel-powered car over an equivalent petrol is no longer the case.
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SNIPQUOTE!
In reply to bbroomlea:-
I thought the rover had a bmw cr diesel engine?
Edited by Dynamic Dave on 29/04/2008 at 13:49
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It's common knowledge that all CR diesels fail in the same way that all Vauxhall Ecotecs do.
My original point, and the point HJ was making, was when CR diesels fail, they can be very expensive to fix whereas petrols generally aren't.
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For what its worth, I have an 8 year old BMW 530d Touring with only 85k miles on. I have had to change a MAF and apart from a vacuum hose and the wastegate getting stuck open I have had no problems from that perspective. I have had a wiring harness loom that rubbed itself against (presumably) the bulkhead and this shorted out my injectors. Can't really be applied to the Diesel Problem. The only other big cost I have had is to the rear air suspension.
My wife has a 3 year old diesel Grandis with the 2,0 VAG PD. That has caused zero problems so far on the engine front but its noisy.
Edited by Webmaster on 30/04/2008 at 02:08
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I have a 52,000 mile Grand Scenic, for which I have the complete service history, both in terms of invoices and checksheets, and the printout from the Renault UK computer which my dealer kindly supplied me with.
As I bought the car while still under warranty, it makes no sense for it not to have gone through the dealer network for all repairs.
I can confirm in 52,000 miles, the engine has had (outside of routine servicing).....
2 glow plugs.
The car itself has a had a couple of things go wrong with it, but none of it relates to the mechanics of the car in any way which continue to start on the button and whisk the car about with refinement, perkiness and economy.
I hope it continues! Of course what the story will be like at 104,000 miles is anyone's guess.
Cheers
DP
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>>I thought the rover had a bmw cr diesel engine?
Yer the 75 did and a £1000 bill for yet another set of high pressure pumps, I had to call it a day and traded it in. It did have 225K on the engine but if I had paid to have the pumps replaced it would have been on the third lot so averaging just over 100K each. From my research and speaking to a mate who works for Ford, common rail reliability is nowhere near previous generation diesels. When its time to renew my Audi, I will probably go back to petrol
The ZR we are getting has the old L series Rover engine which was a development of the old perkins engine I believe - quieter (actually debatable), not as smokey and buckets of torque.
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Its things like this (low mileage car) that make me nervous:
tiny.cc/6HET4
Stumbled across this whilst looking to reply to another thread on Pandas, but it seems relevant to this thread.
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Its pretty much a one off I think with the Multijet. Same poster seems to have had problems with the gearbox too.
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Panda gearboxes seem a bit dodgy (see the thread 'gearbox Panda 100hp').
Its all very well saying the problem is 'a one off', but how many 'one offs' are there? Very difficult to answer, I know, but I don't think things should be dismissed in such a way. After all, how many car owners post their problems on the web, its a very very tiny percentage I think.
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Agree with Screwloose about desperate engineering. Picked up a Golf brochure which stated that specifying a car with DPF is not advised for those doing urban runs and Channel islanders. Crazy when particulates are more of a problem in urban areas.So if you live in London or Jersey and fancy a 170 TDI forget it
The problem is that these targets are foisted on the manufacturers on pain of large fines by those who don't know a thing about engineering. Take Darling saying he wants the new average to be 100g/km rather than 120 which itself is already causing manufacturers problems. Anyone involved in legislating for vehicles shouls have a engineering background in my opinion.
Edited by Mattbod on 29/04/2008 at 17:40
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"but I don't think things should be dismissed in such a way"
qxman, Not intending to be dismissive and i`m sorry if it came over like that.
But of all the woes over on the Fiat Forum there is little on failure of the Multijets injection system. (That`s what I should have written)
I`m ready to switch to one of those 2 cylinder petrol jobs having said that...maybe.. ;)
Regards
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Given Fiat's long histroy of dubious cars, I decided not to buy any new Fiat until the new ranges were tested in at least 5 years' hard usage.
I see my scepticism is justified.
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The Fiat Uno is still on sale in Brazil.... on second thoughts maybe not ;)
Regards;)
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