Fuel Consumption (Petrol vs. Diesel)
- Thread starter triggerthat
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As a student, every saving is crucial.
In terms of performance, having a car which is slightly more powerful yet returns more miles seems a logical step (1.4 RT vs. TD 306).
In terms of breaking even, how about a cheap diesel - sub £1000.
In terms of performance, having a car which is slightly more powerful yet returns more miles seems a logical step (1.4 RT vs. TD 306).
In terms of breaking even, how about a cheap diesel - sub £1000.
Most people I know have a budget to buy the car with, and spend it.. that's why there are so many "Spec me a car for £5K" threads.. which means that purchase prices would be identical, and any fuel savings are a true 'saving', coupled with less depreciation, I'd say most people can have a valid case for a diesel to save money for them, they will spend the budget regardless..
Sure you may get a year older diesel over the petrol equivalent for your budget, but then if people are that 'concious' of age etc, they would go for an even newer one then the petrol equivalent, with a lower spec/ weedier engine..
News cars, I agree, you have to be 'careful' if it's purely a financial decision where the diesel is at a premium, and I am sure there are people that make that mistake.. but secondhand with a fixed budget, you can't go wrong..
Sure you may get a year older diesel over the petrol equivalent for your budget, but then if people are that 'concious' of age etc, they would go for an even newer one then the petrol equivalent, with a lower spec/ weedier engine..
News cars, I agree, you have to be 'careful' if it's purely a financial decision where the diesel is at a premium, and I am sure there are people that make that mistake.. but secondhand with a fixed budget, you can't go wrong..
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People keep saying that TDIs are for lazy people who dont like changing gears but thats not exactly true :/ If anything you have to do more gear changes to keep the revs in the power band :s
Its only if youre not bothered about going fast that you can drive lazily and use the torque available to save you chaning gears when you have to slow down a little
Its only if youre not bothered about going fast that you can drive lazily and use the torque available to save you chaning gears when you have to slow down a little
Phal said:
Yeah, it's a little crazy. People moan about the short power band of Diesels. Well the power on mine is between 2000 and 4500 rpm like most diesels. In a great deal of petrols, the power is between 4000 and 6500 rpm, surely that's the same sized power band - except with the diesel you don't have to rev the nuts off it.
i used to have a 1.9 audi a4 diesel 130 bhp with tweaks.
that got 50mpg wherever i went, usually very quickly too.
my golf 2.0 16v gets about 30 average, is slower than the audi (at the moment)
basically, diesel (engine sizes being similar) is miles cheaper, without a shaddow of a doubt.
fox goes on about diesel being as or more expensive than petrol, from experiance, ive seen that is simply not true, but cannot be arsed to get a calculator out
also. diesels are quieter and have more instant/accessible shove and basically get you down the road quicker (with comparable sized, tuned engines)
that got 50mpg wherever i went, usually very quickly too.
my golf 2.0 16v gets about 30 average, is slower than the audi (at the moment)
basically, diesel (engine sizes being similar) is miles cheaper, without a shaddow of a doubt.
fox goes on about diesel being as or more expensive than petrol, from experiance, ive seen that is simply not true, but cannot be arsed to get a calculator out
also. diesels are quieter and have more instant/accessible shove and basically get you down the road quicker (with comparable sized, tuned engines)
![[TW]Fox](/data/man-of-honor/2009.png){kind=avatar}
k3v said:
See this is the thing. You see those two figures, 52mpg v 35mpg, and assume the diesel is as a result a considerably better buy.
In reality, the saving you make on petrol will be less than some people spend on tyres in a year, for example. I know that sounds daft but the point I am trying to get across is that people place FAR too much emphasis on fuel economy, as if its the main cost of running a vehicle. Whilst it often IS the main cost, it isn't normally a HUGE cost - like I said even running a huge great 3 litre petrol car for a year is 'only' £2000 a year. People think its the be-all and end-all of car decision making and, IMHO, it isn't.
Buy a diesel if you love the way the drive. Some of us do, thats great. But don't restrict your choice only to diesel cars simply becuase you think it will be noticeably cheaper becuase it just won't.
Especially if you have a low budget which pre-dates the modern generation of diesel engines - take Mondeos for example, the 1.8TD is more economical than the 2.0 petrol but the 2.0 petrol is so much better in every way bar economy, and even in economy, the actual difference in cost per year is marginal.
Before deciding you absolutely must get a diesel, do the maths. See what your personal saving would be. If you feel it warrants a diesel, go for it. However don't simply buy a diesel because 'you need to save money' without even bothering to check how much you'd really save becuase its just daft.
Matt82 said:
Actually that is NOT what I say - I say that petrol isnt THAT much more expensive. People simply assume it is - people like yourself, by your own admission you cannot 'be arsed' to actually work out if it really is any cheaper or not
I don't blame you for thinking like that - I did. Infact, I based my purchase decision for my first car on it. I bought a Citroen Xantia 1.9TD. I loved the car, and around town, I got about 34mpg out of it (Bear in mind it was all stop-start and it was an older indirect injection engine). I didnt need to fill up much, I was much better off than getting a petrol engine.
But was I? I did the maths before I bought the Mondeo - prompted by the fact the Mondeo diesel was naff so I thought I'd see if I could afford to run the petrol one.
34mpg over 8000 town miles @ 95p a litre: £1014 a year
25mpg over 8000 town miles @ 92p a litre: £1336 a year
So, the extra cost of running a 'thirsty petrol engine' around town was just £322 - or £26 a month, or just 90p a day. ie, negligable compared to other costs associated with running a car. So I got the petrol one. Before I sat down and worked it out properly I, like you, simply assumed diesel = cheap to run petrol = much more expensive. I dare say most of you here spend more than the additional monthly cost I found of running a petrol car on a single night out! Thats how insignificant the sum can actually be. Chosing one car over another PURELY based on that saving is right up there with basing your £5000 car purchase on which car has the lower tax group - wow, you can save 60 quid a year, etc
As you can see, this is not the case.
Like I said - if you prefer the driving style, then cool, the financial incentive becomes irrelevent. If I could afford a minter I'd buy a 530d Sport not a 530i Sport - but not for reasons of economy.
As for quieter - no, not really. As quiet in certain circumstances - yes, ie at cruise, but generally even with modern turbodiesel technology a diesel engine is louder than a petrol engine. Not hugely, but it's false to state they are quieter.
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Soldato
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Sorry, L0rdMike here. 
Read under for my reply.
Read under for my reply.
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Ok so I got it wrong and posted on the wrong account but I dont care about Passats and diesel cars. 
It wasnt my car I dont know what engine was in it but it had a TDI badge on the back of it.
Was at work and I had to go out and with only 2 seats I had someone just hand over someones car keys over and I was off.
Company cars for the win.
but I dont care about Passats and diesel cars. It wasnt my car I dont know what engine was in it but it had a TDI badge on the back of it.
Was at work and I had to go out and with only 2 seats I had someone just hand over someones car keys over and I was off.
Company cars for the win.
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Here you all go, a definitive document by the AA clearly showing the difference between running costs for petrol and diesel.
http://www.aatrust.com/files/reports/310303_motoringcosts06.pdf
Look at the standing and running costs as pence per mile in the 13k to 20k bracket, it shows that it is dearer to run a diesel for average and below average mileage per annum, but better for higher mileage per annum.
And also, there is not a lot in it between them either.
I think this should hopefully put an end to which is more economical. There is not a great deal in between them and sometimes it is dearer to run a diesel, but not always.
http://www.aatrust.com/files/reports/310303_motoringcosts06.pdf
Look at the standing and running costs as pence per mile in the 13k to 20k bracket, it shows that it is dearer to run a diesel for average and below average mileage per annum, but better for higher mileage per annum.
And also, there is not a lot in it between them either.
I think this should hopefully put an end to which is more economical. There is not a great deal in between them and sometimes it is dearer to run a diesel, but not always.
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[TW]Fox said:Actually that is NOT what I say - I say that petrol isnt THAT much more expensive. People simply assume it is - people like yourself, by your own admission you cannot 'be arsed' to actually work out if it really is any cheaper or not
I don't blame you for thinking like that - I did. Infact, I based my purchase decision for my first car on it. I bought a Citroen Xantia 1.9TD. I loved the car, and around town, I got about 34mpg out of it (Bear in mind it was all stop-start and it was an older indirect injection engine). I didnt need to fill up much, I was much better off than getting a petrol engine.
But was I? I did the maths before I bought the Mondeo - prompted by the fact the Mondeo diesel was naff so I thought I'd see if I could afford to run the petrol one.
34mpg over 8000 town miles @ 95p a litre: £1014 a year
25mpg over 8000 town miles @ 92p a litre: £1336 a year
So, the extra cost of running a 'thirsty petrol engine' around town was just £322 - or £26 a month, or just 90p a day. ie, negligable compared to other costs associated with running a car. So I got the petrol one. Before I sat down and worked it out properly I, like you, simply assumed diesel = cheap to run petrol = much more expensive. I dare say most of you here spend more than the additional monthly cost I found of running a petrol car on a single night out! Thats how insignificant the sum can actually be. Chosing one car over another PURELY based on that saving is right up there with basing your £5000 car purchase on which car has the lower tax group - wow, you can save 60 quid a year, etc
As you can see, this is not the case.
Like I said - if you prefer the driving style, then cool, the financial incentive becomes irrelevent. If I could afford a minter I'd buy a 530d Sport not a 530i Sport - but not for reasons of economy.
As for quieter - no, not really. As quiet in certain circumstances - yes, ie at cruise, but generally even with modern turbodiesel technology a diesel engine is louder than a petrol engine. Not hugely, but it's false to state they are quieter.
even my previous car (the 320cdi) could get 30mpg around town and that was 2 tons of lard with an auto box. your xantia is therefore a terrible example of a diesel, my audi never went down to 34mpg unless it was ill, leaving soot tracks everywhere.
around town it would do 40+mpg all the time. i can remember one trip to alton towers, 100+mph almost all the way, it returned over 50mpg.
my £48 for the tank did 550miles consistently. the golf, not in a million years will match that, is doing well if it can do half that (£40 tank, so maybe a gallon difference).
therefore, if you can get hold of a half decent diesel ie better than a xantia, then youre on for a winner.
i can only justify the golf because i do less miles and i really fancied something to play about with and thrash the living daylights out of
Soldato
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[TW]Fox said:
Whilst I know what your saying hear, and mostly agree, I don't think that looking at the exreme (3 litre motors) really hold up to investigation. I'm looking for a 406 coupe at the moment, and "want" the 3L, but a realistic mpg is around 23. The equivelent Hdi will be pushing 40mpg. On my mileage (about10K pa) that will be around £800. My extra outlay for the tractor will be back in about 18 months, and I hope to keep the car far longer than that.
Servicing costs for large engine cars (especially 6 pots) are often a lot more than hdi equivelents..
I suppose what I'm trying to say is that most of us will get a lot nearer the quoted mpg figures in a Hdi than a 3 litre V6 just because of the way the engines encourage us to drive.
To be honest, if your a £ per mile junkie, go get an lpg car, no fancy common rail tractor will get anywhere near that 60p per litre price difference. (you might have trouble finding a pump when the reserve light is on though
)Matt82 said:
And a modern, direct injection system. The Xantia had a 1.9TD engine which, in design times, dated from the 1980's. On similar trips in the 530d, I get under 30mpg and whilst that wasn't driving like a grandad I wasn't exactly caning it either. My route out of a morning includes negotiating a mile of speed ramps with the engine stone cold, so lots of start-stop-bad-economy driving.
It actually had what was regarded as one of the best diesel engines of its time. It was perfectly healthy, nothing was wrong with it, and it'd do 50mpg on the Motorway.
Your E320 in 2002: £25,000
my Xantia in 2002: £1200
Any more useless comparisons let me know, thanks
aztechnology said:
Why not? It shows worst case scenario - if running a big 3.0 for 15k miles 'only' costs £2k a year in fuel, anything lesser you get the amount will be even smaller..
Thats not really a fair comparison is it? The 2.2 HDi should be compared, roughly, to the 2.2 16v petrol becuase they offer similar performance. The V6 406 Coupe offers considerably better performance than the diesel, it isn't really a like for like comparison.
Plus, although the 2.2 HDi *will* exceed 40mpg with ease, it won't do it if you are driving it in the way that you'd only get 23mpg out of the V6. That suggests caning it/driving it around town and with a combined fuel consumption figure of just 44mpg, you won't be getting 40mpg around town with the HDi. If you are pushing 45mpg from the HDi, you'd probably be getting 28+ from the HDi under similar conditions.
Only if you pay main dealer prices. At the end of the day the only thing a 6 pot requires more of is plugs
Not really fair that, is it? Get a diesel because you'll drive it normally whereas if you get a petrol you'll have some fun with it... errr, hmmm...