Are modern diesels too good?

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Thu 26 Feb 2015 16:24
Are modern diesels too good? - mss1tw

Pootling about today in the Berlingo, it needs winding up to about 3000 rpm (once warmed up) to make good progress. I'm fine with this as I know diesels like to be worked hard.

Makes me wonder if modern hyper-diesels are their own worst enemy, good to drive at below 2000rpm if you want and barely ticking over at legal speeds.

Mine is spinning at 4000rpm at 80mph and that will definitely 'blow the cobwebs out' (always drives better after a long hard run)

They seem over-specified for what they end up doing, even motorway work only uses a fraction of the power except when overtaking.

Having the power in reserve must be nice though....;)

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Thu 26 Feb 2015 18:57
Are modern diesels too good? - gordonbennet

They might have got a bit too clever, or rather too much emission faff on them, for their own good.

Whilst on paper all is rosy, fantastic power, economy, minimal servicing all looks good, in practice is the reality, especially long term durability (and real life economy) living up to the promises.

Not just cars either, we have a new lorry on test, all singeing (tee hee) all dancing euro 6, promises of amazing economy, drives itself i tell yer...well i've known the current driver/test pilot for 29 years as friend and colleague, if i had my own lorries he would first to be poached whatever it cost...the thing won't pull you out of bed and it's drinking fuel like it's life depended on it, plus its already coming up with various dash warnings of impending doom on a daily basis...utter rubbish.

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Thu 26 Feb 2015 19:10
Are modern diesels too good? - mss1tw

Slightly off-topic but what's the deal with AdBlue? Is that an EGR alternative?

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Thu 26 Feb 2015 19:19
Are modern diesels too good? - gordonbennet

Yes, its a urea based mixture injected directly into the hot exhaust, supposed to, among other things, convert nasty nitrogen oxides into relatively harmless products, mainly CO2...i'm fairly sure on this but happy to be put right.

I'm staying in the 90's technology range with me own motors ta, when they eventually ban them it'll be shanks' pony or a bike for me.

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Thu 26 Feb 2015 19:26
Are modern diesels too good? - Alby Back
My boss has recently got himself one of those Porsche Cayenne hybrids. Part electric, part petrol. Still only does around 30mpg in real life as opposed to the 50 or so I get in my large diesel Merc.

If you're doing miles, diesel still wins. Technology will no doubt advance though I suppose.
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Thu 26 Feb 2015 22:01
Are modern diesels too good? - Happy Blue!

Sitting contemplating electric/hybrid cars with a mate we concluded they are a waste of money. Only work for those people doing a low daily mileage and the saving in fuel costs is therefore minimal. And the cars cost a fortune....No point.

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Thu 26 Feb 2015 20:23
Are modern diesels too good? - corax

I'm staying in the 90's technology range with me own motors ta, when they eventually ban them it'll be shanks' pony or a bike for me.

Shanks' pony - had to look that one up.

"...the thing won't pull you out of bed"

That's a good thing isn't it?

I'll only drive a modern diesel if I'm forced to. But there's plenty of good modern petrols to choose from.

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Sat 28 Feb 2015 07:33
Are modern diesels too good? - Bianconeri

I'm staying in the 90's technology range with me own motors ta, when they eventually ban them it'll be shanks' pony or a bike for me.

Shanks' pony - had to look that one up.

"...the thing won't pull you out of bed"

That's a good thing isn't it?

I'll only drive a modern diesel if I'm forced to. But there's plenty of good modern petrols to choose from.

Hear, hear. I get to drive dozens of different cars a year, all pretty new thanks to hire fleet policies, and have that sinking feeling when I realise I've been allocated a diesel! I've even tried them for my own vehicle but always return to petrol. Our 'fleet' has two turbo patrols that are both a delight to drive ( and very economical in normal use ) and an ancient 'normal' petrol that gulps petrol but is wonderful and does only 1500 miles a year do who cares about the cost? We're back to 'cheap' versus 'good' in my opinion.
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Fri 27 Feb 2015 08:51
Are modern diesels too good? - craig-pd130

It's a good point. Turbocharging, advanced injection systems and sophisticated mapping have massively increased torque output over a (relatively) wide rpm range compared with older-generation diesels. But the manufacturers then use VERY tall gear ratios to reduce emissions and maximise economy.

At 80mph my Volvo D4 is spinning at 2,000rpm in 6th, and it will still pull hard from this point if you plant your foot. It is nice being able to surf the wave of torque, but in practice if you worked the engine even moderately hard (i.e. used just 3,000rpm through the gears), you'd be over the NSL in 4th, and automatically losing your licence in 5th and 6th.

So it isn't surprising that non-enthusiast owners experience problems with components getting coked up, etc.

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Fri 27 Feb 2015 09:03
Are modern diesels too good? - Avant

"Pootling about today in the Berlingo, it needs winding up to about 3000 rpm (once warmed up) to make good progress. I'm fine with this as I know diesels like to be worked hard."

Horses for courses isn't it - and both have perhaps changed a bit ove rthe years. The first diesel we had was a Peugeot 205 GRD for SWMBO - we got it mainly the for the low-down pulling power rather than for financial reasons where there wasn't much in it between diesel and petrol. If diesels now need to be worked hard, that advantage has gone.

And now the new wave of economical, torquey petrol engines has led to there being few advantages in having a small diesel car; whereas for people such as Alby who do mega-mileages pounding the motorways, diesel is still ideal.

I suspect that hybrids are really only effective if most of your motoring is in towns and cities.

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Fri 27 Feb 2015 12:45
Are modern diesels too good? - Snakey

I'm looking into a hybrid for my next car purely because a) I want an automatic b) I want to avoid problematic diesels (I would be buying a 3-5 year old car) and c) I don't want to have my trousers pulled down over road tax.

With that, a hybrid seems to fit the bill nicely.

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Fri 27 Feb 2015 14:24
Are modern diesels too good? - craig-pd130

When my previous company car was coming to the end of its lease I looked quite seriously at two hybrids, the Ampera and the Prius+, because the low BIK tax etc was quite interesting.

I didn't like the interior of the Prius+, so ruled it out just on grounds of it not suiting my taste. I did like the look of the Ampera but it's a strict 4-seater, and I often need to carry 5, so I had to rule that out too. It's a pity as the road tests of the Ampera are very positive.

Unfortunately there's a huge price gap between the smaller (Prius, etc) and larger hybrids (like the Volvo V60, which is ludicrously priced). Hopefully this might be addressed, but until then, I'm sticking to diesel.

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Mon 2 Mar 2015 20:53
Are modern diesels too good? - Ed V

Have you tried putting down in writing the annual cost of your motoring. e.g. of depreciation, fuel, road tax etc.

Were you to do so, I'd guess you'd worry less about road tax!

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Fri 27 Feb 2015 14:01
Are modern diesels too good? - mss1tw

Exactly avant - based on what I've read, under-use of a diesel is almost abusing the thing, they are built to be workhorses, whereas petrol engines might not run optimally but it's not as detrimental

The new small petrol turbos tuned for torque/low down power rather than peak bhp seem an ideal replacement.

Edited by mss1tw on 27/02/2015 at 14:02

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Fri 27 Feb 2015 14:36
Are modern diesels too good? - gordonbennet

Under use as you rightly put it didn't used to be a problem with iDi engines, turbo'd or not.

You could stop start them as often as you wanted, poodle about barely off tickover for weeks on end or thrash the living daylights out of it and, so long as you treated them to some decent oil changed regularly and a new cambelt when necessary, would go on without a moments problem for the life of the vehicle in most cases.

Why all of a sudden do you have to thrash the things like gutless undersized petrol engines or they'll die, musn't drive it like a proper Diesel letting it lug or the DMF of cheese will peg out on you before you can blink.

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Fri 27 Feb 2015 14:43
Are modern diesels too good? - mss1tw

Too right GB. Mine 'lugs' superbly, (Hill starts with two BIG off-road motorbikes, on a heavy old pig iron trailer, 2000ft above sea level on a Pyrenean hill? No problem!) but slowly.

Don't want to hold people up any more than necessary though! So I give it a bit of welly.

To give the equivalent workout to a modern engine would need an autobahn, I think!

Edited by mss1tw on 27/02/2015 at 14:44

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Sat 28 Feb 2015 13:00
Are modern diesels too good? - barney100

I can't get over 2000 revs in mine or I risk a goodly speeding fine but it means relaxed cruising at legal limits with the power to overtake when needed.

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Sat 28 Feb 2015 14:11
Are modern diesels too good? - mss1tw

I suppose you could enter a tractor pull event... :-)

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Sat 28 Feb 2015 14:37
Are modern diesels too good? - Bianconeri

I can't get over 2000 revs in mine or I risk a goodly speeding fine but it means relaxed cruising at legal limits with the power to overtake when needed.

I have a couple of patrols like that, they make a really nice noise as the revs rise too!
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Mon 2 Mar 2015 21:32
Are modern diesels too good? - Bromptonaut

Intersting thread as I have the same Berlingo model as mss and a more recent 63 reg 1.6Hdi/115.

Never felt a need to 'thrash' the 1.9D in normal running.

It pulls like a train from a bit over 1500 revs. Above 3k it gets coa*** and noisy so tend to select that as change up point. Ocasionally rev it further on climbs, regular one is getting past trucks where they're in the crawler lane on s/b A5 out of Kilsby. Otherwise limit it to 3k as that's near 70 in top and, while it will do 80/130kphwith foot on boards, you an see the fuel gauge dropping.

If it drops out of the power band you know as vibration rises to point where each detonation is felt through body and steering.

The new one also pulls like a train from 1500. It's still smooth well over 3k but no need to go there as thats well over 70 in top and little need to use on gradients either, even with a tonne of caravan on the back.

It's oddity though is that it will drop out of the power band without any sensory feedback. Like OP's it's been to Pyrenees. Very easy to get on a climb, slow on throttle to round a hairpin and then apply power to find it completely flat footed. The eletronics presumably control fuel to stop if smoking or overloading the big/small ends in way juddering detonations do on an old fashioned IDI might do..

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