Fuel Consumption (Petrol vs. Diesel)
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![[TW]Fox](/data/man-of-honor/2009.png){kind=avatar}
Soldato
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[TW]Fox said:
I'll just start again by saying I agree with most of what your saying
, looking at the Petrol / Diesel argument, you can only look at each individual case, and the costs involved can be close. To be honest, I expect to loose as much to deprecieation as to fuel. having said that....because at this end of the market, the differences can be variable, a 330d and 330i are similar performance and reasonably close in the numbers. Find 320d/i's with similar performances though the gap can widen considerably (upto 18mpg. I could use that to illustrate a bigger saving on the diesel side....
[TW]Fox said:
cut the bit about drivin style and performance....
he he... I'm not comparing them... I want to buy the best performance I can get. If I could get the V6 past the other half I would, but she thinks one the cars we have should average better than 30mpg. I strongly suspect that any Hdi i get will be having it's chips fried.... I considered getting a v6 converted to run on lpg, but I'm not confident enough that lpg conversions on big v6's have all the problems sorted out.
[TW]Fox said:Only if you pay main dealer prices. At the end of the day the only thing a 6 pot requires more of is plugs
until the Cam belt needs a change
[TW]Fox said:
Err no, thats not what I mean. You say in a later post, you like the lazy torque of diesels, so do I. I also like that rush when a big VVT engine comes on cam. Whichever I have, I'll use. One of them will cripple fuel consumption far more than the other.
I really shouldn't give a stuff about fuel economy anymore as my daily commute will soon drop from 36 miles a day to 3 miles and anything on top of that I'll get 40ppm for.
Despite that I'm going for a diesel for my next motor. Even though my fuel costs are mre than paid for the less I spend in fuel costs the more I get in my pocket. My milage will drop but will still be around 15,000 a year. Maybe more but its hard to judge as I will be moving house, work place and my role in the company all at once.
If I save £500 a year then effectively thats a months mortgage (all bar £90) we haven't got to find.
Its funny, when I was working part time at uni with no real outgoings £500 seemed like a hell of a lot less money than it does now I'm working full time on 'not too bad' money
EDIT- Forgot to say that I'll be getting a diesel when the 306 dies, changing in order to make a saving makes no sense as Fox pointed out.
Despite that I'm going for a diesel for my next motor. Even though my fuel costs are mre than paid for the less I spend in fuel costs the more I get in my pocket. My milage will drop but will still be around 15,000 a year. Maybe more but its hard to judge as I will be moving house, work place and my role in the company all at once.
If I save £500 a year then effectively thats a months mortgage (all bar £90) we haven't got to find.
Its funny, when I was working part time at uni with no real outgoings £500 seemed like a hell of a lot less money than it does now I'm working full time on 'not too bad' money
EDIT- Forgot to say that I'll be getting a diesel when the 306 dies, changing in order to make a saving makes no sense as Fox pointed out.
wasnt you only pottering about in the 530d for a weekend or a week? i gotta agree about the power delivery on the larger diesels
in regard to the engine comparisons, my original comparison was a xantia diesel and an audi diesel, you were saying that from your experiance the xantia gave terrible consumption around town.
i was pointing out that your posts in this thread are based upon flawed experiance. the original comparison was the audi, that got 45mpg everywhere whereas your xantia only got 34mpg around town. as a bi-comparison, the lard mercedes still bettered 30mpg and is an engine that is 50% larger attached to a car thats a similar increase in mass again.
your posts about "diesels are not that much cheaper" should come with a disclaimer stating "the above is only true if you plan to use a poor diesel that can only manage 34mpg around town".
there is no possible way that you could say i am in even a broadly similar financial position when it comes to buying petrol for my gofl compared to when i was buying diesel for the audi.
regardless of the difference in price of the two fuels (less than 5%, less again if you buy high octane fuel), the audi acheived 50% more mpg consistently and provided similar if not better performance.
hence, from exeriance of a not-too-shabby diesel and a not-too-shabby petrol engine of comparable capacity, you are miles better off with the diesel
in regard to the engine comparisons, my original comparison was a xantia diesel and an audi diesel, you were saying that from your experiance the xantia gave terrible consumption around town.
i was pointing out that your posts in this thread are based upon flawed experiance. the original comparison was the audi, that got 45mpg everywhere whereas your xantia only got 34mpg around town. as a bi-comparison, the lard mercedes still bettered 30mpg and is an engine that is 50% larger attached to a car thats a similar increase in mass again.
your posts about "diesels are not that much cheaper" should come with a disclaimer stating "the above is only true if you plan to use a poor diesel that can only manage 34mpg around town".
there is no possible way that you could say i am in even a broadly similar financial position when it comes to buying petrol for my gofl compared to when i was buying diesel for the audi.
regardless of the difference in price of the two fuels (less than 5%, less again if you buy high octane fuel), the audi acheived 50% more mpg consistently and provided similar if not better performance.
hence, from exeriance of a not-too-shabby diesel and a not-too-shabby petrol engine of comparable capacity, you are miles better off with the diesel
Matt82 said:
I guess I've probably driven it for about a month now in total and covered approximately 2500 miles in it, including 2 weeks of just town-use. It is a brilliant car and I can think of many reasons to buy one - saving thousands on fuel is, however, not one of them.
I personally don't feel mid 30's from a old indirect injection engine around town to be 'terrible'. I feel it is par for the course.
I refuse to believe you can get 45mpg from an Audi diesel in PURE town work - ie, stop start stop start through traffic with a cold engine etc.
Like **** should they. I've given NUMEORUS different figures, infact only once used the figures from my own experience. Using quoted fuel consumption figures from manufacturers as well, you can see the difference isn't staggering. The way some people on this forum talk is as if you can save thousands a year by moving to a diesel. This is frankly rubbish - it is my intention to point this out wherever possible.
Even magic diesel Audi's wont save you thousands if you do about 10k a year around town.
Well, if we discount the fact your Audi had a magic engine, I doubt the difference is huge. Plus, how much did your Golf cost to buy? How much was the Audi... thats my main point. Normally you pay more.. For me, it is approximately £2000 more if I wish to buy a 2001 530d over a 2001 530i. I'll never make that back through the better fuel consumption.
I need to go and buy a magic Audi it seems becuase I just cannot agree with that statement, UNLESS you do high mileage. I've always used the 'unless you do high mileage' caveat becuase once your annual mileage is north of about 15k a year the diesel makes more and more sense.
I'm trying to explain to the people who do normal or low mileage that NO, diesel does not suddenly mean you'll be much better off.
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Was that directed at me?[TW]Fox said:Why not use the same logic to buy a 1.4 Punto instead? Thats like the cost of 5 takeaway pizza's you dont have to find when buying tax
All I was saying is that £500 to me seems like a decent saving and when I look at changing cars I'll more than likely be getting a diesel. I'll be shopping with a set budget so the fact that an xx reg petrol would be £xxxx less than a xx reg diesel is irrelevant. I'll buy an older diesel. I'd be more confident in a diesel enigine that is a year older with an extra 20,000 miles on the clock lasting the test of time than the petrol anyway.
£500 may be small change to you (which I find odd for someone at uni) but in real world terms its a fair sum.
lordrobs said:
£500 on its own is certainly not 'small change' but spread over a year it's impact is considerably less than 'omg £500' and as such not, IMHO anyway (Mind you all of what I say in this thread is just my take on things) basing car purchase decision on solely..
And for all those who argue that well its all very well saying diesel costs more but most people simply say 'I will spend £5000 on a car' and buy a £5k car rather than a 2002 car, well hows about this...
Spend £4500 on a car + £500 extra on fuel = same as spending £5k on a diesel, you'd probably end up with a car the same age and mileage as a 5k diesel anyway.... etc
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[TW]Fox said:
my aim is not to "make the money back by saving money on buying diesel fuel over petrol fuel".
when you sell a car, you are almost bound to lose money, infact there are plenty of instances of diesels depreciating less than their petrol counterparts.
therefore, you buy a diesel car for more, you sell it for more, therefore cancelling out the higher initial outlay.
whilst you own the car, though, a 500 mile trip in the audi would cost a tank, £45. the golf, to cover the same distance, would be atleast 1.5 tanks, £65, if not more, as thrashing it drastically reduces mpg, as too does town driving.
FOX:-
I agree with what your saying to a point. Your right, fuel should really be looked at on a per month basis as its not like you have to pay for your years fuel up front. In that regard my "same as a months mortgage" comment is out of context.
I was just questioning the way you made it sound like it was 'only' £500, probably just my interpretation of what you were saying.
I see your logic with the £5k diesel = £4.5k petrol + £500 fuel. I hadn't looked at it in that way, I guess a lot of people don't which is why they are so popular
Having said all that I'll still be going for a diesel next time round. I think my milage will be over the break even point and there is a chance that I'll be going up and down the country a fair bit so the power on tap feel that they have would be quite appealing.
I agree with what your saying to a point. Your right, fuel should really be looked at on a per month basis as its not like you have to pay for your years fuel up front. In that regard my "same as a months mortgage" comment is out of context.
I was just questioning the way you made it sound like it was 'only' £500, probably just my interpretation of what you were saying.
I see your logic with the £5k diesel = £4.5k petrol + £500 fuel. I hadn't looked at it in that way, I guess a lot of people don't which is why they are so popular
Having said all that I'll still be going for a diesel next time round. I think my milage will be over the break even point and there is a chance that I'll be going up and down the country a fair bit so the power on tap feel that they have would be quite appealing.
I’m not so happy with Fox’s BMW calcs, using his numbers of:
BMW 530i Sport: 29mpg combined. 01/51: £12600
BMW 530d Sport: 39mpg combined. 01/51: £14280
Difference £1680 (not £2000!)
Assume petrol is 91.9p a litre, diesel is 94.9p a litre (Prices from my local garage).
10k in the petrol costs (10,000 miles / 29mpg ) x 4.54 litres/gal x 0.919 = £1439 per year.
10k in the diesel costs (10,000 miles / 39mpg ) x 4.54 litres/gal x 0.949 = £1105 per year.
So a saving of £334 per year or £1002 over 3 years. The difference between the cars was only £1680 so the diesel has cost £679 more.
According to Fox the diesel would still be worth £1000 more than the petrol after three years so after selling the cars on the diesel owner has an extra £321 in his back pocket.
Doing the same calculation for 15k miles per year comes out with £2158 for the petrol and £1657 for the diesel, leaving the diesel owner with an extra £823 after three years.
Add to that £823 the fact that less of a finite resource has been used which has to be a good thing and the diesel is the winner in my eyes.
The other point to make is about new cars - All diesels will break even and then work out cheaper than their petrol versions long before the end of their lives so on average drivers of diesels cars get a better deal. Maybe some individual users don't see the cost benefit (due to not actually driving the thing!) but over say a life of 150,000 miles the diesel (50mpg, 95p) will have saved over the petrol (35mpg, 92p) some £17,900 petrol - £12,939 = £4,961. Since £5,000 is less than the price difference of the new car there is real saving that will have been shared between the respective owners.
BMW 530i Sport: 29mpg combined. 01/51: £12600
BMW 530d Sport: 39mpg combined. 01/51: £14280
Difference £1680 (not £2000!)
Assume petrol is 91.9p a litre, diesel is 94.9p a litre (Prices from my local garage).
10k in the petrol costs (10,000 miles / 29mpg ) x 4.54 litres/gal x 0.919 = £1439 per year.
10k in the diesel costs (10,000 miles / 39mpg ) x 4.54 litres/gal x 0.949 = £1105 per year.
So a saving of £334 per year or £1002 over 3 years. The difference between the cars was only £1680 so the diesel has cost £679 more.
According to Fox the diesel would still be worth £1000 more than the petrol after three years so after selling the cars on the diesel owner has an extra £321 in his back pocket.
Doing the same calculation for 15k miles per year comes out with £2158 for the petrol and £1657 for the diesel, leaving the diesel owner with an extra £823 after three years.
Add to that £823 the fact that less of a finite resource has been used which has to be a good thing and the diesel is the winner in my eyes.
The other point to make is about new cars - All diesels will break even and then work out cheaper than their petrol versions long before the end of their lives so on average drivers of diesels cars get a better deal. Maybe some individual users don't see the cost benefit (due to not actually driving the thing!) but over say a life of 150,000 miles the diesel (50mpg, 95p) will have saved over the petrol (35mpg, 92p) some £17,900 petrol - £12,939 = £4,961. Since £5,000 is less than the price difference of the new car there is real saving that will have been shared between the respective owners.
Course it's not true, my lazy man diesel has 6 gears and I change gears more in the diesel than the petrol. Diesels do allow you to avoid some changes but certainly doesn't mean you have to.Phal said:
[TW]Fox said:
I agree with a lot of what you are saying fox, but my counter argumement and the reason I went for a diesel is the fact that the £500 will depreciate more slowly when spent on a car (especially a diesel) than it will when spent on fuel.
On top of this, I usually plan to keep a car longer than 12 months and the majority of my driving is done at times when you appreciate creature comforts, a slush box and effortless torque more than youd appreciate racing suspension and a high reving engine.
dilated said:
This I will never argue against - my point 'against' diesels is purely financial. If you simply prefer the way they drive, then no amount of figures will make any difference to you - irrespective of how much more it does or doesn't cost, if thats the way you enjoy driving, thats the way to spend the money
I am simply suggesting to those people who begrudging feel that they MUST buy a diesel that no, actually, they needn't. If you actually WANT to buy a diesel, then go ahead, there are many benefits, it's not purely a financial thing.
We all know those numbers are wrong and Fox knows it too, from any angle buying diesel makes sense and will save money. Despite his biased way of looking at "the beemer thing" there are few obvious omissions in the "financial point" outlook:
- For Fox even 1/3rd difference in fuel consumption is not relevant if he has to pay more than double fuel savings as initial difference in price of the car. However to most buyers the fact they have extra grand at point of purchase doesn't neccessarily mean they will not feel 1/3 more in fuel costs every month hitting their wallet. As you said, 32mpg and 50 litre tank means you feel like you are parked by the fuel pump all the time and suddenly you can't even make it to Amsterdam and back on one tank of fuel in mid size hatchback..
- Price difference between used diesels and petrols are not always as prenounced as between beemers. In my case the difference between 6 speed 136 bhp 2.2 litre diesel Almera and 116 bhp 5 speed 1.8 petrol model with the same trim was initially set @ £1300, but shrunk to a mere £500 after a year so when I bought my pre reg car there wasn't a single argument to buy petrol, it was weaker, less economical and not much cheaper... Also servicing of my diesel car is only £30 extra compared to petrol but gives me 3000 more miles between services. And it's true for most brands outside VAG and beemer range - up to a grand difference in price...
Then you have to look at depreciation factors of cars bought as used, the gap in value between a diesel car kept for two years and during that time going from 75k to 95k and petrol car with identical mileage will grow and widen with every mile closer to 100k, simply because in market perception diesel car with 100k on the clock is abouth "half way though" its life whereas 100k petrol car is on its mythical "last legs". Like it or not that's how market behaves. Come to sell a 120-150k diesel Focus will attract fairly good part exchange tag, whereas most dealers will offer a bag of crisps and used up set of mats for a 150k petrol Focus.
- For Fox even 1/3rd difference in fuel consumption is not relevant if he has to pay more than double fuel savings as initial difference in price of the car. However to most buyers the fact they have extra grand at point of purchase doesn't neccessarily mean they will not feel 1/3 more in fuel costs every month hitting their wallet. As you said, 32mpg and 50 litre tank means you feel like you are parked by the fuel pump all the time and suddenly you can't even make it to Amsterdam and back on one tank of fuel in mid size hatchback..
- Price difference between used diesels and petrols are not always as prenounced as between beemers. In my case the difference between 6 speed 136 bhp 2.2 litre diesel Almera and 116 bhp 5 speed 1.8 petrol model with the same trim was initially set @ £1300, but shrunk to a mere £500 after a year so when I bought my pre reg car there wasn't a single argument to buy petrol, it was weaker, less economical and not much cheaper... Also servicing of my diesel car is only £30 extra compared to petrol but gives me 3000 more miles between services. And it's true for most brands outside VAG and beemer range - up to a grand difference in price...
Then you have to look at depreciation factors of cars bought as used, the gap in value between a diesel car kept for two years and during that time going from 75k to 95k and petrol car with identical mileage will grow and widen with every mile closer to 100k, simply because in market perception diesel car with 100k on the clock is abouth "half way though" its life whereas 100k petrol car is on its mythical "last legs". Like it or not that's how market behaves. Come to sell a 120-150k diesel Focus will attract fairly good part exchange tag, whereas most dealers will offer a bag of crisps and used up set of mats for a 150k petrol Focus.
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Associate
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Firegod said:35mpg from the mk1 1.4 clio is not bad at all! That's one of the better results I've heard. Coming from a fellow owner, I'm lucky if I get 20mpg, but the tank is only 11 gallons. Not big at all. If you got 350 miles from it that's fine.
EDIT: Also factor in the age now of those kind of cars and the efficiency will be degraded.
Lucky to get 20mpg from a 1.4 engine?
I have yet to get under 19mpg from my 3.2 litre, straight six, 2 ton, 16 year old, automatic and that includes a tank of only town driving where i got the 19mpg.
From my 1.6 306 i never got worse than 34mpg even with a full tank of town driving only.
I drive pretty quick and accelerate fast, but ease off fairly early and cruise towards roundabouts/red lights rather than braking last minute
Matt82 said:
You what?
Since when? Even the latest most amazing diesels still suffer from being noisy when cold. The Honda 2.2 CDti is the quietest smoothest diesel around (well pretty much anyway), even that isn't as quiet as a petrol (although it comes close)
I'm not against Diesels but purchase price is a big factor, if i was buying a modern car i'd give it good consider it though
