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Worth paying a prem...
 

[Closed] Worth paying a premium for a diesel engine?

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I'd say if you plan doing less than 15K a year and aren't bothered about a torquey engine for the hills go for the petrol with only 10% (ish) of the mileage the diesel has.


 
Posted : 09/02/2010 10:23 pm
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The TDi will be a lot more relaxing to drive due to the extra torque and will use less fuel than the petrol in everyday driving, the 1.4 will feel a bit gutless. Not sure how many miles you do a year but that diesel has done nearly 30000 a year from new, might be worth having a real good luck over the service history and check for cambelt change etc. They are both fairly cheap for what was a £12k+ car new.


 
Posted : 09/02/2010 10:27 pm
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Diesel used to be more reliable but that's not necessarily the case as I can testify after 4 new injectors on a 3.5yr old diesel. (Plus all the manufacturers use the same injectors so all pretty poor)

Good points is the amount of torque, good acceleration now to match a petrol, fuel consumption, starts every time from cold instantly.

Bad points: no more reliable than petrols and errr that's about it.

On paying the extra I'd say it's only woth it if you're going to do a whole load of miles every year, not just for average mileage.

So pretty much in agreement with Carlosg then......


 
Posted : 09/02/2010 10:28 pm
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wasn't planning on either, just half heartedly looking for something cheep'n'crap to supplement the MG midget..

mpg doesn't relay bother me, I can get to my parents and back in the midget for £40, and that's filling it with Shell jungle juice 🙂


 
Posted : 09/02/2010 10:29 pm
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Love the look of these wee Skodas 8)

I personally would go for the petrol regardless of the milage you do as your getting a low miler for not alot of cash also its a very simple engine with not much to go wrong unlike high milage(for age) diesel


 
Posted : 09/02/2010 10:34 pm
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I only have a diesel because I do 20k miles a year, but even then it was a bit marginal cost-wise - for the Civic it's down to a 1.8 petrol or 2.2 diesel, both making the same power, but the diesel feels more powerful more of the time because you don't need to rev it everywhere. Lots of people seem to be buying diesels these days just for that reason.

Diesels tend to be slightly lower on CO2 (so fall in a lower tax bracket) and can be cheaper to insure too. Against that, servicing tends to be more and there's usually lots of expensive bits - turbos, injectors, dual-mass flywheels and the like - which tend to fail at some point once out of warranty. Oh, and in the winter they take an age to warm up enough for the heater to work.

Those two cars are a bit of an extreme example, but the 1.9PD will be a load quicker than the figures suggest, and it's a trim level up which gets a load of other niceties too.


 
Posted : 09/02/2010 10:35 pm
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Turbo Diesels are good on the motorway and grunty. They're often a bit frustrating for 'spirited' driving though and NOT actually as fast as people think they are. An equivalently grunty petrol will be thirsty.

The cost benefit isn't that great unless you do a lot of mileage and if the fuel pump, turbo, injectors etc. pack in then the benefit will be instantly lost.

I have a diesel but may go back to a non-turbo petrol the next time I buy a car.


 
Posted : 09/02/2010 10:42 pm
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Definitely needs to be 15K+ miles a year to be worth it.
If like me you do more like 30K a year, then it's miles cheaper in the long run.


 
Posted : 09/02/2010 10:42 pm
 mrmo
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i don't care about the cost savings/increases, i prefer diesel because of the way they drive, more relaxed.


 
Posted : 09/02/2010 10:53 pm
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I used to drive 75,000 year, all in Diesels, I now only do 24,000, splite between the van and car, both Diesels,one with 113,000 on the clock, one with 95,000 on the clock, neither burn any oil and run sweet as a nut, if you service them regular, dont thrash the NUTS of them they will look after you well, I changed to Diesels over 25 years ago and would NEVER go back to a petrol.


 
Posted : 09/02/2010 10:54 pm
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The question is, how much of a man will you feel in a 1.4 skoda?


 
Posted : 09/02/2010 10:55 pm
 DrP
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Very good article on this in the Parker guide online.
Compares equivalent Diesel and Petrol models - it's an interesting read as some diesel models will NEVER be financially viable (i.e will never break even!).

That's the reason we went for a petrol engine - cheaper to buy, and we simply don't do the miles needed to justify it.

DrP


 
Posted : 09/02/2010 10:59 pm
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How much of a 'man' would you feel in a 1.4 anything? Unless it's a TSi, or a Boka Negra.


 
Posted : 09/02/2010 11:01 pm
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We tow a caravan & a diesel engine is loads better for that. If we didn't tow we'd have petrol as nice & quiet.


 
Posted : 09/02/2010 11:09 pm
 br
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The last time I had a diesel (Xantia 1.9TD), it was a company car 'forced' on me due to the miles I did - colleagues who did less could have petrols...

Do the sums, work out the costs.


 
Posted : 09/02/2010 11:16 pm
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ok you get more mpg, but when you include the CO2 released making diesel it works out pretty much even

Where d'you get that from?

As for spirited driving.. new common rail VAG engine pulls like hell up to the red line, in fact increases in power as you get up there just like a petrol. But unlike a petrol, it also works at 1200 rpm too. So win/win.


 
Posted : 09/02/2010 11:21 pm
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I drive a 1.5 midget, I'm used to driving slowly everywhere :p


 
Posted : 09/02/2010 11:25 pm
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OK - so what about in France where the Diesel is about 30% cheaper than petrol..

what should I buy? doing about 10,000 miles / year...


 
Posted : 09/02/2010 11:25 pm
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Where d'you get that from?

I design oil refineries for a living

There isn't enough diesel in the world to supply demand, so you pass the heavy oils through a hydro cracker which is a huge great big reactor the size of a medium sized office block, stuffed full of a very expensive catalyst at very very very high temperatures and pressure.

Even the pure diesel streams from crude oil need hydro treating under much harsher conditions than petrol.


 
Posted : 09/02/2010 11:30 pm
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It's worth noting that diesel and petrol both come from the same source ie crude oil, which is refined to produce loads of different things. So you could argue that the energy cost of producing diesel is nil if you are going to produce all the other things anyway..... you can't produce diesel on its own.


 
Posted : 09/02/2010 11:35 pm
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I design oil refineries for a living

It was a geniune question not a bolshy stw I think you're wrong statement. Really, I'd like to read about it.


 
Posted : 09/02/2010 11:36 pm
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As for replacing injectors - petrols have them too. Also they have spark plugs, HT ignition systems etc. Plus a petrol engine's turned over 50% more in its life so 50% more piston strokes and whatnot.


 
Posted : 09/02/2010 11:40 pm
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Plus if you care about CO2 emissions you can put biodiesel in your diesel 🙂


 
Posted : 09/02/2010 11:41 pm
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To get over the inherent problems with emissions and 'refinement', diesel injection systems work at extremely high pressures which can be harsh on pumps and injectors.

Turbos (on whatever type of engine) wear out, quickly if not looked after.

For want of a better phrase, a modern high-output TD engine is basically in a 'higher state of tune' than a similarly-sized petrol.


 
Posted : 09/02/2010 11:42 pm
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Have you driven either of those cars?

I would hazard a guess that the 1.4 will be choresomely slow, but you are paying a whole lot more for a car with many more miles on the clock if you take the diesel option.

For what it's worth, the 1.9TDi in my Ibiza (almost same engine, but with more poke) has been fine for the 90k miles I have done in it over the last 3 yrs 4 months. Only engine related thing i have had replaced was an intercooler pipe.
The 1.9TDi is clattery on start-up, but fine once warm. It does take a while to warm up & might not be the best choice if you are doing lots of short journies.
As for servicing costs, my Ibiza has cost me no more to service than my old MkIII 1.4 8v Fiesta, even though it has 55bhp more & 3x the torque (although it gets through tyres quicker). Even the cambelt isn't that expensive to get changed (60k mile service with cambelt changge totalled £270).
I've certainly not experience this 'diesels cost more to service' thing that people talk about.


 
Posted : 09/02/2010 11:49 pm
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In fairness, the 1.9TDI is actually a good engine and more 'robust' than more modern, common-rail engines.


 
Posted : 09/02/2010 11:51 pm
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Diesels are worse for air quality if that concerns you at all. Driving them does keep my research in business though....


 
Posted : 09/02/2010 11:52 pm
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i agree with the diesels more relaxing to drive statement above

i had a 1.8 diesel fiesta when i passed my test - it was ace i sold it for 100 quid with 200k on the clock and rusty as buggery- arrived with 90k ....

moved onto petrol 90bhp 1.6 engine - lasted from 60k to 80k before headgasket went

then a 120bhp hyundai lantra - hand me down from parents it lasted 3 weeks befor electrics died. but it could shift if you "drove it"

back into a diesel 1.9 pug van and it cant overtake for shit so i drive more sensibly - leave earlier and use less fuel for this reason alone - i know i cant just floor it and accelerate quicker and use more fuel im restricted to 16 seconds minimum 0-60

im also changing gears alot less - hills - pah i laugh at hills.

insurance is a git though


 
Posted : 09/02/2010 11:59 pm
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For want of a better phrase, a modern high-output TD engine is basically in a 'higher state of tune' than a similarly-sized petrol.

So how come all the ultra-mileage cars are diesels? Mine's still a baby at 136k (would be a lot more if I'd carried on doing the ~18k average mileage I was when I got it - yesterday I filled up for the first time this year!)


 
Posted : 10/02/2010 12:42 am
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It was a geniune question not a bolshy stw I think you're wrong statement. Really, I'd like to read about it.

couldn't pull up an article on it, just something someone at work mentioned and I've no real reason not to believe it, refining diesel is much more energy intensive than refining petrol, here's the pocess simplified

Petrol:

Crude->[atmospheric distillation]->naphtha->[hydrotreater]->[splitter](just another distillation column)

heavy naphtha and light naphtha are then treated by isomerisation and platforming and blended to make the various grades of petrol.

All in all its mainly low pressures and temperatures, nothing too extreme.

Diesel, some of it comes out the atmospheric column, but no where near enough, so you take the heavy fractions and 'crack' them to make lighter stuff, depending on the market this usually means diesel (in America they use FCC reactors which produce more petrol). This involves seriously high temperatures and pressures and lots of energy.

Obviously the carbon footprint of your diesel depends on the oil used in the refinery, the refinery configuration, and the market demands.


 
Posted : 10/02/2010 1:11 am
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The internet disagrees with me on this one, maybe he was talking bollocks, although most of the internet evidence is ranting at taxation and claims that petrol is easier to refine which just runs counter to what I would say.


 
Posted : 10/02/2010 1:18 am
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The other problem with Diesels is the NOx output in the exhaust. As greenhouse gasses go, they're the daddy.
But still, as the owner of a 13 year old 1.9 diesel polo with not a shred of electronics in the engine, I choose to ignore that.
48-55mpg and it would happily run on warmed up butter.


 
Posted : 10/02/2010 1:31 am
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NOx is not a greenhouse gas per se but it contributes to tropospheric ozone and also can go to N2O, both of which are. NOx can also reduce greenhouse gases by going to OH which shortens the lifetime of greenhouse gases like CH4 so its swings and roundabouts.


 
Posted : 10/02/2010 1:44 am
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Yep. It's only a pollutant if you put it in the wrong place. Unfortunately my car doesn't have a 10 mile high exhaust pipe!


 
Posted : 10/02/2010 2:00 am
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Diesel, some of it comes out the atmospheric column, but no where near enough, so you take the heavy fractions and 'crack' them to make lighter stuff,

Hmm, I didn't know about this. It's true though that the carbon footprint of diesel would depend on the amount of extraction and of what type of crude for diesel and other purposes.

I had a look at the VW site last night comparing petrol and diesel on the basis that they probably have some of the most efficient petrol engines. In Passats the petrol compares reasonably favourably with diesel, but not at all in Golfs.

The energy cost of producing diesel is another argument in favour of petrol hybrids, is it not?


 
Posted : 10/02/2010 9:54 am
 tron
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The 1.4 Skoda will be slightly slower than the 1.9 diesel in terms of out and out power.

That said, I don't like the way diesels drive (if I want relaxed, I'll get a car with a V8, LPG and an autobox), and I don't like the complication and weight of them. Dual mass flywheels, extremely high pressure injection systems and a grand's worth of emissions kit do not make for the kind of reliability people talk about. It's always been something of a myth that diesels are more long lived than petrols - maybe in the pre fuel injection days when petrol cars suffered from over rich mixtures and lots of bore wash, but not now.

So my view is that I'd go for petrol every time. If I were buying new, and doing 30k a year, it might work out for me to buy a diesel. Buying second hand and doing sane mileage, you might save a quid or two a week on fuel, but you can be landed with a £500 bill at any time if the DMF, fuel pumps or DPF pack up.

There's a bloke quoted in this article on the amount of CO2 produced by refining diesel:
http://www.telegraph.co.uk/motoring/green-motoring/7166444/Is-diesel-dead.html


 
Posted : 10/02/2010 9:56 am
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as others depends om the milage or towing so do some sums
As for those questioning whow much of a man you would feel in a 1.4 I am so sorry for you that your masculinity is so fragile that if you dont have a large powerful car it somehow feels threatened..the answer for me would clearly be more of a man than you would as my sense of being a man is not linked to the cc of the car I drive.


 
Posted : 10/02/2010 11:44 am
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For those people saying that Diesel has a higher fuel pressure than petrol isn't strictly true. New lean burn tech (stratified charge) where direct injection of the fuel into the commbustion chamber is utilised run similar fuel pressure's to that of diesel of about 120 bar. So the diesel/petrol argument there is kinda taken out of the equation.
Sure Normal indirect multipoint this could be taken into consideration


 
Posted : 10/02/2010 12:06 pm
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New lean burn tech (stratified charge) where direct injection of the fuel into the commbustion chamber is utilised run similar fuel pressure's to that of diesel of about 120 bar

I think that Common Rail diesel pressure is of the order of [b]1000-2000 [/b]bar.


 
Posted : 10/02/2010 12:50 pm
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As for those questioning whow much of a man you would feel in a 1.4 I am so sorry for you that your masculinity is so fragile that if you dont have a large powerful car it somehow feels threatened..the answer for me would clearly be more of a man than you would as my sense of being a man is not linked to the cc of the car I drive.

Quite right. In order to prove your manhood you simply have to have kiddy seats in the back and a "baby on board" sticker.


 
Posted : 10/02/2010 1:43 pm
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The 1.4 Skoda will be slightly slower than the 1.9 diesel in terms of out and out power.

0-60 maybe, but the 1.4 will feel way way slower - as I can testify. In a 1.4 you'll be forever having to wedge it in 3rd to get anything at all to happen. In the D you'll be able to squeeze the pedal and get pushed forwards whatever gear you are in.

As for reliability of diesels, it's not a myth, it may be a touch out of date though. In the old days a diesel benefited from being overbuilt, and running at low revs all their lives, but they didn't have to worry about a HT injection system. So no damp start problems, no mixture problems, no carburettor, no fuel quality issues, no spark plug issues, no HT leads etc etc etc.


 
Posted : 10/02/2010 3:10 pm
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PS can't believe the Honda 2.2 iCDTI isn't in the favourite diesel engine list on that telegraph article.

PPS I'd only drive petrol hybrid if I could tow with it.


 
Posted : 10/02/2010 3:12 pm
 tron
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As for reliability of diesels, it's not a myth, it may be a touch out of date though. In the old days a diesel benefited from being overbuilt, and running at low revs all their lives, but they didn't have to worry about a HT injection system. So no damp start problems, no mixture problems, no carburettor, no fuel quality issues, no spark plug issues, no HT leads etc etc etc.

Spark plugs tend to last at the very least 20k, and fairly often 50k these days, depending on what plug's specified. About the same as glow-plugs. EFI has done away with cold start issues etc. The only thing that a petrol has to go wrong that a diesel doesn't have an equivalent for is HT leads, and that's a fairly rare occurence (with the exception of Mondeos of a certain vintage).

On the other hand, diesels have bits that petrols don't, and seem to manage to lunch Dual Mass Flywheels at a massive rate compared to petrol cars. And the bits that pack up on diesels are expensive!


 
Posted : 10/02/2010 3:41 pm
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Spark plugs tend to last at the very least 20k, and fairly often 50k these days, depending on what plug's specified. About the same as glow-plugs.

Strangely my glow plugs manage rather more than that (think I had to have them done at ~90k).

On the other hand, diesels have bits that petrols don't

Such as?

I don't have a DMF flywheel either - them being unreliable is a whole separate issue.


 
Posted : 10/02/2010 4:09 pm
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