Diesel vs Petrol?

[jbw]

I currently drive an a3 1.8T Quattro (8L) but have recently been looking at selling up and getting a diesel a3 (8P).
I drive 40-50 miles a day and I'm finding the quattro costly but I'm having a hard time working out whether I'd actually save much cash. Has anyone recently swapped from petrol to diesel and noticed a difference financially or just got some advice on the subject?

cheers,
J

 

[jojo]

Financially, changing cars is wasting money, you will save money in the long run keeping the 1.8T and keep filling with petrol until it dies!

 

[Kontraband]

Didnt we have a long thread on the relative merits of each fuel over different types of travel??

LIke diesel was only worthwhile if you were doing the higher miles to make its a good financial decision?? Or am I thinking of some other convo??

 

[SteveTDCi]

Diesel does have it benefits but at the moment i'm looking at going back to petrol, a lot of the new smaller petrol engines are getting better all the time, i had a 207cc 1.6 120ps as a hire car last year and driven in the same way as my Tdi it covered similiar MPG, so if you went for something like the 207 GTI 175 I reckon 34mpg should be possible, i'm currentlt getting 40mpg out of my A3 and i'm will to lose 6mpg when I will save over £5 per tank of fuel.

 

[Amchlolor]

Barring a lottery win and a supercar, I doubt I'll ever go back to petrol.
My car has 200bhp and 305lb/ft of torque, standard.
It also did Aberdeen to Brighton (582 miles door to door) on one tank of fuel.
Nuff said, really.

 

[AndyMac]

130 TDi A4 - easily the best decision I made, 650-700 miles per tank, 48mpg over the last 72 hours of driving, and nice lazy torque all the way. 34mpg? what on earth is that?

 

[simch]

I just did an airport run in an a3q 20tdi 170.

Cruising at 80 the DIS showed 39.5mpg total of 120miles.
I was not that impressed fuel economy wise, the old PD130 golfs would have done at least 49mpg on same journey!
Diesel is at least 11% more pricey, so the 39.5 is eqivalent to about 35 mpg from a petrol. I think the pence per mile is maybe only 1-2p per mile less on the diesel car now compared to an equiv petrol!
Which is madness as diesel is cheaper to make!

 

[Nilz]

I have petrol at the mo and do mainly motorway miles and am getting about 32mpg out of an S3, i have looked into getting diesel, but with the cost of it being so high, compared to petrol, i just dont know whether it would be worth the change, although a trip to london on the weekend was a bit of an eye opener, the father in law has a Passat 130tdi sport and we both filled up before we left, my full tank was showing 380 miles on the DIS, his was showing 550!! Then when we go there his was still showing that, where as mine was considerably less!!!

 

[simch]

I think the older pd engines were awesome on the juice, but the 2litre 170, with dpf and quattro really seems to sap the economy.
It's a nice solid car, with some nice bits on it, but I was not "that" impressed at how it went if I am honest. My missus has a chipped mondeo estate car 2litre 130 and it felt no faster than that, and the mondeo pulls from earlier in the rev range too.

Again, a real nice car, but not as frugal as I thought it may be. Maybe needs to loosen up still!

 

[Amchlolor]

I just did an airport run in an a3q 20tdi 170.

Cruising at 80 the DIS showed 39.5mpg total of 120miles.

That is poor.
Cruising at 100mph, I was getting 49mpg from my 200bhp diesel.
I agree that in the case you've given, the gap between diesel and petrol is less obvious.
It seems Audi need to improve the efficiency of their engines somewhat.

 

[dsmclark40v]

I've just had the pleasure of driving a range rover tdv8 for the last two days and the on board computer was saying 31mpg-ish from motorway driving at 80ish and thats a big heavy car and went like stink! sadly had to give it back today. still i think with the cost of diesel most of the saving is gone concidering that diesels seem to cost more to buy in the first place. plus i prefer the sound of a petrol engine

 

[jojo]

130 TDi A4 - easily the best decision I made, 650-700 miles per tank, 48mpg over the last 72 hours of driving, and nice lazy torque all the way. 34mpg? what on earth is that?

That's excellent mpg for am A4 Andy, mainly motorway driving I'm guessing, do you have the Aircon on also? My Passat Estate TDi averages around 40mpg with mixed town and A road driving with the CC on constantly, this drops to 36mpg driving around town 90% of the time. I did get a respectable 46mpg on the way to Devon and back with the CC set on economy, so the ****** thing saps quite a lot of fuel!
Figures are all brim to brim figures, DIS is waay out on my car.

 

[buckas]

had a jetta 1.9 tdi for when we went touring round scotland a few weeks back

1800 miles for £190 of diesel, 60+mpg , my car would have easily cost double that, cost less to fill up than my a3 due to smaller fuel tank, not to mention road tax difference (£100) insurance cheaper the lot, had a hooooooge boot too, lovely car, could've of driven it forever, much more comfortable than my sports seats!

 

[AndyMac]

I never turn the cc off, unless I'm cruising on fumes to the next petrol station. My mate has the new shape passat TDi (140 IIRC) as a company car and he only gets petrol mpg but he has got a digital right foot.
Above figures are all mainly motorway, but even in town it only drops to 38-40mpg. These are all DIS figures, but pretty spot on last time I did a brim to brim check.
Your 18" reps will probably be having more of an effect than the CC. One reason I stuck with the stock alloys, that and the price of rubber - £69 fitted for Goodyear Excellence, as opposed to £109 for my 2.8Q. The TDi is purely a working car as the missus runs it as a company vehicle (co. car opt out scheme) and it definately earns its keep even at 190k miles!

 

[jojo]

The TDi is purely a working car as the missus runs it as a company vehicle (co. car opt out scheme) and it definately earns its keep even at 190k miles!

Mine's at 160k miles and I had the cambelt and service done last week! Apart from wear and tear and a couple of sensors, the Passat has been the most reliable car I have owned... with regards to the wheels, I'm sure you are right, but I have an alloy wheel fetish, so that is something I won't be changing. :icon_thumright:

 

[Macduff]

Which is madness as diesel is cheaper to make!

But apparently you only get half the quantity of diesel from a barrel of oil compared with petrol so the cheaper production costs are wiped out.

 

[jbw]

I should have mentioned I'm looking at about £1-1.5k difference in selling the petrol quattro and getting a tdi. I mostly do motorway miles. The TDI's I'm looking at are around 3 years newer, done slightly less miles and tax is cheaper. USing my limited maths skills I've worked out I can save around £800 a year on fuel and tax if I purchase a diesel and stick to doing the same mileage.

 

[AndyMac]

New turbo was the only thing we've had done in the 90k miles of ownership apart from routine stuff like cambelt etc. and I'm convinced that only let go because of the ****** longlife oil on AVS before we switched over to 10k services.

 

[smitch]

i never use my S4 other than on weekends and it still costs a ****** fortune in fuel. 18 mpg or less usually, i'm gonna get shot of it and buy a golf TDI.

I'll probably only fill it up once every other month.

Watch me get bored and buy a 2nd car though.....

 

[benw123]

I should have mentioned I'm looking at about £1-1.5k difference in selling the petrol quattro and getting a tdi. I mostly do motorway miles. The TDI's I'm looking at are around 3 years newer, done slightly less miles and tax is cheaper. USing my limited maths skills I've worked out I can save around £800 a year on fuel and tax if I purchase a diesel and stick to doing the same mileage.

What fuel economy are you currently getting from the TQ? This will help you work out if you're going to make a saving.

You've probably done this already: if you're doing 50 miles a day, then you're working week commute is 250 miles. Suppose you're getting 30mpg from your TQ; that means you're using 8.33 gallons per week. Multiply that by 4.54 to get litres (37.83) and then multiply again by the cost of unleaded (say £1.12p) which gives you a weekly total of £42.37 commuting costs.

Now, in an A3 8P 2.0TDI 140 over the same motorway-based distance, I think you're likely to see almost 50mpg but lets say you only get 40mpg (as a total worst case estimate). Same calculation: over 250 miles, that's 6.25 gallons or 28.38 litres, and assuming diesel is around £1.22p a litre, that's a weekly cost of £34.62. So it is almost a £7 saving per week. 45mpg in the diesel would be £30.77, and if you were really light-footed and got 50mpg, that's gonna be £27.69 or a saving of nearly £15 per week. Pretty good.

You get the idea - adjust the mpg and fuel prices to those that are relevant to your car and area and you'll get a decent estimate of what savings you might make. Diesel is more pricey than petrol but the difference has really got to climb before you'll ever save money with unleaded, although my Prius does ... but that's another story!

 

[jbw]

What fuel economy are you currently getting from the TQ? This will help you work out if you're going to make a saving.

You've probably done this already: if you're doing 50 miles a day, then you're working week commute is 250 miles. Suppose you're getting 30mpg from your TQ; that means you're using 8.33 gallons per week. Multiply that by 4.54 to get litres (37.83) and then multiply again by the cost of unleaded (say £1.12p) which gives you a weekly total of £42.37 commuting costs.

Now, in an A3 8P 2.0TDI 140 over the same motorway-based distance, I think you're likely to see almost 50mpg but lets say you only get 40mpg (as a total worst case estimate). Same calculation: over 250 miles, that's 6.25 gallons or 28.38 litres, and assuming diesel is around £1.22p a litre, that's a weekly cost of £34.62. So it is almost a £7 saving per week. 45mpg in the diesel would be £30.77, and if you were really light-footed and got 50mpg, that's gonna be £27.69 or a saving of nearly £15 per week. Pretty good.

You get the idea - adjust the mpg and fuel prices to those that are relevant to your car and area and you'll get a decent estimate of what savings you might make. Diesel is more pricey than petrol but the difference has really got to climb before you'll ever save money with unleaded, although my Prius does ... but that's another story!

I just went here and based on what I'm paying and an average MPG of 50 for a tdi it gave me a difference of around £800 a year. My TQ currently states an average MPG of 29.6 (that's based on quite a few months driving).

cheers,
J

 

[benw123]

That's a good estimate then. If you get 50mpg with my calculations, you'll save £15 a week, or roughly £750 per year, then around £30-50 in road tax due to the lower CO2 a diesel engine produces; so it is roughly £800 a year saved. Enough to make a real difference!

 

[-Ju-]

I've recently changed from The 8P 3.2 to a BMW 330cd. The BM is 6 months older(54 plate) and cost me £800 to change. I do average miles, circa 10/11k a year and I recon I'm saving £20 a week in fuel costs. It's also cheaper to tax and insure and hopefully will have better residuals.
Performance wise, apart from the loss of Quattro there's nothing in it.

Never thought I'd move to the dark side, but at the moment I've no regrets!

 

[MintyS3]

Im lucky enough that my drive into my workplace is short and quite often at very low speed (30-60mph) and with no stop starts. So whether its a petrol or a diesel I get decent fuel consumption.

Ny old fabia was great. £45 to fill up and only once a month. Filling up 12 times in a year is nothing but it was nowhere near as good on the dual or motorways. If my journeys included this kind of travel I may not own an S3 and instead gone for a diesel cruiser like an A4 with decent long gears.

 

[Neilybabs]

What fuel economy are you currently getting from the TQ? This will help you work out if you're going to make a saving.

You've probably done this already: if you're doing 50 miles a day, then you're working week commute is 250 miles. Suppose you're getting 30mpg from your TQ; that means you're using 8.33 gallons per week. Multiply that by 4.54 to get litres (37.83) and then multiply again by the cost of unleaded (say £1.12p) which gives you a weekly total of £42.37 commuting costs.

Now, in an A3 8P 2.0TDI 140 over the same motorway-based distance, I think you're likely to see almost 50mpg but lets say you only get 40mpg (as a total worst case estimate). Same calculation: over 250 miles, that's 6.25 gallons or 28.38 litres, and assuming diesel is around £1.22p a litre, that's a weekly cost of £34.62. So it is almost a £7 saving per week. 45mpg in the diesel would be £30.77, and if you were really light-footed and got 50mpg, that's gonna be £27.69 or a saving of nearly £15 per week. Pretty good.

You get the idea - adjust the mpg and fuel prices to those that are relevant to your car and area and you'll get a decent estimate of what savings you might make. Diesel is more pricey than petrol but the difference has really got to climb before you'll ever save money with unleaded, although my Prius does ... but that's another story!

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