Modern diesels - is there really a problem? - Waino
Three years ago I was thinking that I would, at about now, be replacing my old petrol Mondy with a TDCI version. BUT, in the past few years, I have read so many reports about expensive problems that I have been thoroughly dissuaded. And then again, other drivers seem to swear by 'em.

I've just returned from filling up with petrol down at the local Sainsbury's. The dithering lady in front was filling a small green can with what I assumed to be unleaded. She seemed to be spilling quite a bit down the side of the can and then when she'd filled it, she re-fuelled the car with, as far as I can recall, the same stuff. My only thought at the time was that she was filling the can for the lawn-mower - and it was going down as 'expenses'!

After paying, she drove away in the large Volvo estate and my wife said "hang on, wasn't that a diesel car - it was a D5 - what was she putting in the can?'.

Maybe we'd got the wrong end of the stick, but it's seeing something like that which puts me right off a s/h diesel. And all these diesels that develop problems in later life ......... how many of those are the result of an earlier mis-fueling?
Modern diesels - is there really a problem? - oilrag
Scroll down this Waino and see if it gives more confidence in buying used ;)

tinyurl.com/6rjgos

Regards ;)
Modern diesels - is there really a problem? - Waino
Blimey, Oily, I wouldn't touch one with a bargepole now!

I'd have to look closely at the maths and see if a new one would be worthwhile.
Modern diesels - is there really a problem? - PhilW
"I wouldn't touch one with a bargepole now!"

And yet, our Xantia HDi Exclusive, 2000 model, bought in 2002 with 60k on the clock is stilll going strong - nearly 100k on the clock now and due to have the caravan hitched on the back in mid July for a month's tour of France. Reason for low mileage since purchase is that wife drives it to work about a mile or so (don't ask) every morning. And then we go for a blast with a 'van on the back every year. And what has engine required in that time? Cambelt change and a few oil changes. That's it.
I'm just waiting for a C6 to come up second hand - or maybe a new C5 - second hand - preferably a diesel.



Modern diesels - is there really a problem? - Waino
It's just that I wondered if the reports of 'dodgy' diesels had come about as the result of earlier mis-fueling incidents. There are many reports of diesels going on for years, so clearly they can't all be bad - maybe they are the ones that haven't been mis-fueled?
Modern diesels - is there really a problem? - adverse camber
Waino

common rail diesels are new technology - very high pressure systems and very intolerant of things like misfueling. The older diesels were very tolerant. Hence it became 'common knowledge' that any diesel could have used chip fat/ tesco veg oil / whatever put in. Anf that putting petrol in wouldnt do any real damage. That just isnt true with the newer engines.
Plus as the number of diesels on the road has grown so fast lots of people (esp in pool cars) have suddenly been exposed to the horrid smelly noisy things for the first time and they have the idea that they run on anything, dont need proper maintenance etc.

And of course there are some systems that seem to be made of sticky backed plastic and uhu.

(A two diesel owner writes...)
Modern diesels - is there really a problem? - MikeTorque
We have 2 TDCi's, zero problems. I've heard of plenty of others with zero problems.

As long as you have them properly serviced and use good quality fuel and don't drive the nuts off them you should have a reliable form of transport.
Modern diesels - is there really a problem? - nick
If I wanted a diesel I'd buy one new or nearly new with a couple of years manufacturer's warranty left. Once a modern diesel has had two or three owners and is a few years old I think the risk of there having been a misfuelling episode is too great. You will probably be ok, but the cost if you're not is huge.
Modern diesels - is there really a problem? - colinh
With the current diesel prices I wonder if there'll be a trend back to petrol - and in a year to 18 months we can look forward to "modern petrols - is there really a problem?" threads after all the misfuelling of petrols from ex-diesel owners?
Modern diesels - is there really a problem? - Roly93
With the current diesel prices I wonder if there'll be a trend back to petrol
- and in a year to 18 months we can look forward to "modern petrols
- is there really a problem?" threads after all the misfuelling of petrols from ex-diesel
owners?

Yes the case is looking a bit flakey for diesels now. Personally I have never had an engine related problem in 7 years of driving 3 different diesels. But given that diesel is 15p a litre more than petrol in some cases.
Given my current best local fuel prices my sums say that assuming I would either drive an average 2 litre petrol car or my 2.0 TDI, I would get 32 mpg and 45 mpg respectively on an identical journey down the M4. This equates to 15.8p a mile and 12.6p a mile.
However, if the previously strong residuals of diesels start to faulter you will need to do a lot of mileage now to justify diesel.
I think it is a shame to penalise a source of fuel that generates so much less CO2 per mile thah the alternative, as Mike Rutherford pointed out on TV the other day.
Modern diesels - is there really a problem? - cattleman6
My 1999 Seat Toledo 1.9 TDiSE still going fabulously with 156,000 miles on the clock. It may last another few years.The engine drives exactly the way you want and over 60mph on long runs.
Modern diesels - is there really a problem? - gordonbennet
Ah Cattleman, was only wondering where you were thismorning, must be telepathic.

Yes, my lads toledo diesel is going strong too, despite his cruel driving, its done about 130k i think and runs very well, but whilst his subara was having a full engine rebuild, he found it lacking as it didn't get from 30 to 80 in 3 seconds flat....kids. That reminds me its almost done the thousand miles since rebuild, he'll be changing the oil any time, i hope he doesn't invite me out for a test flight!!

He's going to run it into the ground, will you do the same.
Just out of interest whats your service regime regarding oil changes, cambelts etc.
Modern diesels - is there really a problem? - DP
The Toledo TDI is the Barcelona taxi drivers favourite (in a fetching black with yellow doors livery). On my various visits I've been in many of these cars with over 400,000 km (250k miles) on the clock and they still seem fine.

No better advert for a car in my opinion than a taxi drivers' following.

Cheers
DP

Modern diesels - is there really a problem? - drbe
tinyurl.com/6rjgos


Could someone explain to me who these people are who feel the need to tell the world of the minutiae of their private lives?

Perhaps if she had spent a little less time composing that "blog" (if that is what it is called) and a little more time checking that she is using the correct pump in filling stations, fewer people would have had their lives disrupted.

Edited by drbe on 23/05/2008 at 09:57

Modern diesels - is there really a problem? - FP
A couple of points:

"common rail diesels are new technology"

I suppose that depends on how old "new" is. My understanding is that common rail technology has been around for many years. I thought it first appeared in very big diesels in the 1940s (ships and locomotives), was developed in the late sixties and early seventies and used in commercial vehicles from 1995, with the first car manufacturer to use the system being Fiat in 1997.

I've made the point before regarding the scare stories of misfuelling diesels; there seems to be little hard evidence of long-term problems resulting from this. Certainly some components in some cars will encounter major damage immediately - otherwise, it seems, the majority carry on unaffected once the fuel has been flushed through and (if your luck is out) the fuel pump replaced.

I'm beginning to think "urban myth" here. Correct me, someone?
Modern diesels - is there really a problem? - zookeeper
with the price of diesel at the moment im suprised how much of the stuff ends up on the garage forcourt floor , then onto my shoes , then into the car !!!
Modern diesels - is there really a problem? - spikeyhead {p}
I bought my tdci 20 months ago with 98k miles on it.

Its now got 146k miles on it and apart from a water and power steering pump issue hasn't missed a beat.
Modern diesels - is there really a problem? - scotty
Its now got 146k miles on it and apart from a water and power steering
pump issue hasn't missed a beat.


... ah but ...

Bought my 530D last July with 87K on it. I've added another 16K and have just incurred a £1,000 bill to sort out worn injectors.
Modern diesels - is there really a problem? - b308
I've driven nearly 100k with the VAG PD engines with no engine probs whatsoever - but what does that prove in isolation? - we are a very small % of diesel car owners (even with the people we know) so our views are hardly likely to be typical of the norm... especially as it is well known that people like to moan, and the internet is the ideal platform for moaning!
Modern diesels - is there really a problem? - fitnessqueen
I have a Ford Focus 2002 TDCi- was owned by my dad before me and has full service history and no history of misfuelling. Had no problems at all until the glow plug lamp started to flash occasionally. Have just returned from the diesel specialist who has informed me it needs a new fuel injector pump and injectors and will cost nearly £2K. My dad thinks it might be because I use supermarket fuel.
Modern diesels - is there really a problem? - drivewell
I think this 'supermarket fuel' line is just a cop-out. The fuel sold by supermarkets must meet the minimum standards specified by the manufacturers. Can you imagine the lawsuits if it didn't!

I'm sorry, but welcome to the world of common rail diesels!

Mine is out of manufacturers warranty at the end of June, and it will either be going, or else I'll be buying a comprehensive warranty package.
Modern diesels - is there really a problem? - smokescreen
I just discovered mine (Xsara HDi) doesnt have the ticking timebomb of a DMF clutch, nor a variable vane turbo... for whatever reason, PSA decided not to fit one to the Xsaras?!

Still have the common rail Bosch fuel system, but I certainly dont hear much about them failing often, and I'm mechanically sympathetic so that might help.
Modern diesels - is there really a problem? - b308
the ticking timebomb
a variable vane turbo...


Eh? What ticking timebomb??

I know that a local taxi firm we use have a fleet of Superbs dating from 2002 many with over 160k, some (including one I was in recently) with over 200k and they report no problems...

First I've heard of problem with the PD's variable vane turbo.....

Modern diesels - is there really a problem? - b308
>> the ticking timebomb
>> a variable vane turbo...
Eh? What ticking timebomb??


Actually to be fair I was on the Briskoda site not so long aga and they were discussing blown turbos - but 99% of the problems were with ones that had been chipped/remapped, if kept standard they tend to be just as reliable as any other part of the car....

Has anyone else considered that the problem might be more to this than inherent design/manufacture faults? Its an increasing trend, and anyone whos had a blown turbo is hardly likely to admit to fitting a tuning box if they are trying to get their money back, are they!
Modern diesels - is there really a problem? - 659FBE
The Superb uses the "old" VAG PD diesel which, correctly treated is very reliable.

I suspect the originator of this thread is referring to more modern common rail offerings. As an ex diesel engineer, there are in my view, some aspects of this problem which are quite straightforward - although they don't make comfortable reading.

The essence of efficient diesel operation is to inject the fuel at as high a pressure as possible. This is done by pressurising the fuel using a punp or injector piston in a closely fitting sleeve. As the pressures are so high, a roller type follower has to be used to provide the reciprocating motion for the piston. This applies to any diesel fuel system.

Commercial and very large engines have always been designed for long life so it makes sense to lubricate the cam and roller follower with engine oil - a far better lubricant than fuel. Consequently, large in-line pumps are oil lubricated from the engine and of course, unit injectors (VAG PD) are fully lubricated from the engine oil system.

It is my belief that the lubricity of fuel is insufficient to ensure the reliable operation of the very high pressure systems (usually common rail) now in use and any shortcomings of manufacture and maintenance will quickly cause grief. As with failing cambelts, there is a strong statistical factor in this.

So, I would not buy a modern fuel-lubricated diesel - I'll take good care of my VAG PD.

659.
Modern diesels - is there really a problem? - b308
I suspect the originator of this thread is referring to more modern common rail offerings.


Smokescreen specifically mentioned "variable vane turbos" - I thought that they were a VAG PD engine turbo, not CR - or have they spread to other makes now?

Edited by b308 on 24/05/2008 at 11:34

Modern diesels - is there really a problem? - smokescreen
They've spread to common rail engines too, along with petrol turbos. They dont appear to be as vulnerable as the DMF, but as always, dependant on mechanic sympathy from the driver.
Modern diesels - is there really a problem? - GenevaJohn
659 and injection doc - any views on the Vauxhall 1.7 cdti common in recent Astras and Corsas ?? Vauxhall always seem to get left out of this VW PD and Ford TDCi debate....
Cheers
Modern diesels - is there really a problem? - Galad
>any views on the Vauxhall 1.7 cdti common in recent Astras and Corsas ?? Vauxhall always seem to get left out of this VW PD and Ford TDCi debate....>

Is it because they are really Fiats? I've learned from this site GM/Saab/Fiat share the same diesel lump

A work colleague has been waxing lyrical about his new Saab 1.9TD, until I suggested that it could be a 'Fiat worse then death.......' He's gone very quiet all of a sudden and has been seen poking around in the engine bay for tell-tale signs of Italian probably in the vain hope of spottinga prancing horse.........
Modern diesels - is there really a problem? - smokescreen
Funnily enough the FIAT/GM developed Diesels (JTD range) rarely ever get a mention in the technical forums in terms of problems. They're used in a wide range of cars, too.
Modern diesels - is there really a problem? - injection doc
well drivewell you won't convince me! I have been involved in fuel tetsing & I will leave it at that!.
The most common cause of CR failures is caused by those that allow the fuel tank to run very low before refill.( this causes air to enter the HP pump shortning its life ) I never run below 1/4 tank.
Petrol inadvertantley put in the tank will also cripple the system as it washes away the lubricating properties of diesel. So whilst the car may still run damage to the HP pump will of occured.
I always use a well known branded fuel but not supermarket! I use injector cleaner avery 3-5000 miles ( snake oil ) That has a high quality lubricant in the addative & this help to lubricate the pumps.
I have run TDCi's for years mostly covering 250+ miles a day & in the last 7 years has one injector recoded! & thats it. I have never had turbo failure or injector,or fuel system or even cylinder head failure. I do admit to driving it carefully when cold & allowing it too cool when hot before switching off & using very high grade engine oil, but as it works for me I will stick to the same recipe.
I Doc
Modern diesels - is there really a problem? - gordonbennet
659 and I Doc.

I'm one of those, according to some, gullible fools who uses snake oil in the guise of millers diesel power plus and latterly power plus 4.

I was talking to a chap who worked for Cummins but who worked on smaller diesels too (this many years ago) that the lowering of the sulphur content in fuel was a big backward step in the lubricity of derv, and he'd seen many ruined pumps in the time after.
I had been using millers anyway, and have done so for years mainly for that very reason.

In your opinions does the lubricant effect of millers help to replace whats been lost.

Not going off topic but interested to know whether you skilled chaps have views on this.

Modern diesels - is there really a problem? - prm72
I too use millers in my cars for the lubrication reasons, i was ok with it in my old vectra dti because the manual stated that you could use additives with that engine, but my 05 volvo D5's manual states that NO additives must be used, but would it still be ok to use the small amount of millers that dilutes with the diesel in every tank?, i personally cant see what could be damaged but you more knowlegable people could possibly answer this question.
Modern diesels - is there really a problem? - 659FBE
Additives can certainly improve the lubricity of diesel fuel - in most cases 100:1 addition of 2 stroke oil will have the same effect for a lot less money.

This misses the point though - diesel engines are specified in Europe to run on fuel to EN590 and any engine which cannot do this is a failure. Additives are not generally sanctioned by engine manufacturers (VAG expressly advise against their use) and unlike oils and fuels, carry no specification. So, in my book, they're snake oil.

A well designed engine has to run for an agreed useful lifetime with the specified fuel and oil - that's all.

659.

Edited by 659FBE on 24/05/2008 at 12:53

Modern diesels - is there really a problem? - gordonbennet
Thanks 659, as i can get the millers by the gallon can for very reasonable price i'll carry on, i trust you were agreeing its good for the use of.

I understand your point about an engine being supposedly designed with a fuel in mind, but as we are hearing often, some don't seem to do so well, a little extra lubricant gives hopefully an extra chance of long term reliability.
Modern diesels - is there really a problem? - Kevin Phillips-Bong!
I don't think there is a problem with the engines per se but the 15p per litre difference in fuel prices is making the maths of diesel versus petrol very flaky.

That said, reliable as the Honda has been I'm not sure I'll keep it beyond 3 years (when it will have 90k up anyway).
Modern diesels - is there really a problem? - DP
We have a Grand Scenic with the 1.9dCi engine, and in 52,000 miles the fuel system has never given a second's trouble, at least that I or Renault's service database is aware of. A split wastegate hose and two glowplugs have been the only non-routine attention the engine has needed. It goes well, returns well over 40 mpg in a near 1600kg lump of lard, hardly uses a drop of oil, and pulls well through the entire rev range. Apart from a little clatter on cold, it's also very refined.

I think the issue is not so much the frequency of problems, but the cost when they occur. Parts are expensive, and they need specialist knowledge which can be far beyond the capabilities of some main dealers technicians.

Cheers
DP

Edited by DP on 24/05/2008 at 09:54

Modern diesels - is there really a problem? - oldlag
To all those that think TDCIs are wonderful and somehow the owners are the problem
I had a Ford TDCI from new never wrong fuelled it allways had it servcied at the dealer plus oil change mid year.
It did 22K in 4 years then one day it refused to start.
The garage bills (Ford Dealer) were circa £1900, and in six months the car still played up by refusing to start every so often - the dealer couldnt solve it.
I got sick of having it recovered and paying huge bills.
I did what most do in this situation and went out and got a petrol car.
The Ford dealer let my problem TDCI go to auction despite the fact it as immaculate and had just 22K on the clock.
OK my petrol Ford is not so nice to drive as the TDCI but it starts everytime and it doesnt cost me garage bills of over £1000 each time.
Why I ask myself do those who have run TDCIs for years with no problems seemingly refuse to believe TDCIs can cause this grief and just blame the owners ?
Modern diesels - is there really a problem? - b308
Why I ask myself do those who have run TDCIs for years with no problems
seemingly refuse to believe TDCIs can cause this grief and just blame the owners ?


Or why do some drivers who have had problems seem to think that those problems are endemic in all similar cars - some cars have problems, some don't, thats life!

22k in 4 years seems awfully low - I'd have thought that a petrol would have been a better buy in the first place for that sort of mileage, O?
Modern diesels - is there really a problem? - Alby Back
It does seem to be something of a mystery. As I have mentioned on here, seemingly ad nauseam, I know of several TDCI powered cars, including my own examples, which have consistantly and faultlessly achieved huge mileages.

If there was a basic design fault surely it would affect all of them eventually? It really does rather strongly point to the way they are treated in use doesn't it?

No offence intended, just remain puzzled as to why some people never seem to have any bother with them if they really are that bad.
Modern diesels - is there really a problem? - injection doc
well oldlag, I can sympathise with you as no one wants a car that causes this much grief, but where did you used to buy your fuel & did you ever let it run below 1/4 tank. A very good & reliable scoure tells me this is the number 1 weakness.
I would of thought that with the milage you were covering a petrol would of been the solution anyway. Did you not extend your warranty after 3 years? I have had countless tdci's & run 2 at present & as mentioned before cover vast milages without a hint of a problem & in the last 7 years & mostly covering 45-60k a year only ever had one injector recoded!
IJ
 

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