Diesel vs Petrol

oedipus

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Ok, please excuse ignorance but when the diesel vs petrol issue comes up the first recourse is to the expected mileage. I do 20-22k per year and yes I would expect to be pointed to a diesel because as I see it the higher price is offset by the mpg. BUT, if the cost of fuel were taken out of the equation are there other reasons why you would go for diesel with a high mileage (I intend to keep the car for 8-10 years so expect to notch up 160-200k)? Durability? Lower maintenance costs? Anything else?
 
I'm not sure the maintenance costs are lower... you have DPF and DMF to worry about and maintain these days! I think they tend to last longer overall though, and from my point of view I prefer the way they drive and are better for towing, which I do occasionally. Lower revs as well which I prefer.
 
In Germany there are two - and only two - reasons to buy a Diesel:

1) you love to drive over 200 km/h on the Autobahn all the time
2) you do absolutely huge miles (and we are talking 50.000+ km/year here)

Otherwise it's simply not worth it. Initial costs are way higher (roughly 2-3k), insurance is way more expensive (~50%), tax is more expensive (200-400%), maintenance costs are higher - and it's a Diesel which stinks and makes diesel noises. I did the calculations when deciding on my car for about 25.000km a year and the 1.4 CoD was the way to go.
Not sure about insurance and tax for you guys though.

Disclaimer: as always, your opinion might differ and that's fine.
 
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Tax here is generally cheaper for diesels because CO2 emissions are lower. Not sure on insurance.
 
Well for me it came down to where I live.
PCP wise very little difference in a 1.4 deal and 1.6TDI as the residual is higher on the TDI.
I live in the Peak District so i'm up and down big hills all the time and the TDI just pulls me
up the hills rather than revving the balls off a 1.4.
I now prefer the low end torque the TDI gives me, i'd find it hard to go back to petrol.
 
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The turbo petrols have good low end torque - a lot of the low end torque of a diesel is because they're all turbocharged after all. Peak torque on the current petrols is <2000 rpm across the range.

I don't think maintenance and durability are going to be significantly different between the two with modern engines - there's a lot of go wrong either way. Diesels are sturdily built but petrols are mechanically a bit simpler and there's no DPF to worry about. Also with the worry about NOx starting to kick off now diesels may lose their better tax status. It's much harder to misfuel a petrol as well. ;)
 
I believe that the A3 now has a system to stop you misfuelling the diesel as well, though I'm not entirely sure.
 
I love the petrols but modern diesels are great for cross country blasting and still returning good mpg,
 
Tax here is generally cheaper for diesels because CO2 emissions are lower. Not sure on insurance.

1.4 COD costs 20 quid a year to tax ;)

And to answer your question... the only reason to go for a diesel is fuel economy. Other than that most thing sway in favour of the petrol engine.
 
£30 a year for the Sportback according to the configurator
 
You die hard petrol heads need to drive a torquey v6/v8 diesel then you will forget about petrol engines altogether ! The torque is what makes a diesel effortless to drive- fuel economy is just a bonus !
 
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I believe that the A3 now has a system to stop you misfuelling the diesel as well, though I'm not entirely sure.
Can anyone confirm this? Coming from Ford, which have the excellent, capless refuelling system called Easyfuel I had thought I'd quite miss it's ease
 
You die hard petrol heads need to drive a torquey v6/v8 diesel then you will forget about petrol engines altogether ! The torque is what makes a diesel effortless to drive- fuel economy is just a bonus !

But where's the fun in having to change up at 4000? ;)
 
You die hard petrol heads need to drive a torquey v6/v8 diesel then you will forget about petrol engines altogether ! The torque is what makes a diesel effortless to drive- fuel economy is just a bonus !
I see! That's why no S and RS models use Diesel engines :p
 
My first Audi was an S3 and I would normally choose petrol every time but moved onto an A5 3.0tdi due to mileage/economy, great engine & quick, but didn't have quite the same fun feeling as the S3/petrol. With petrols now becoming more efficient they make a much better case for themselves. I am looking for a new car and would really like the S3 SB or Saloon but with 2 kids it is just that bit too small so next best choice is the BiTdi for me.
 
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Doing 20-22k miles per year I can't see the DPF becoming an issue at all.
 
Well for me it came down to where I live.
PCP wise very little difference in a 1.4 deal and 1.6TDI as the residual is higher on the TDI.
I live in the Peak District so i'm up and down big hills all the time and the TDI just pulls me
up the hills rather than revving the balls off a 1.4.
I now prefer the low end torque the TDI gives me, i'd find it hard to go back to petrol.

The 1.4 petrol engine in the A3 has the same torque as the 1.6 diesel at a similar rpm, thus the 1.4 would be better because it has more power...
 
I see! That's why no S and RS models use Diesel engines :p
It's because of "purists" like yourselves that they did not do the r8 v12 tdi, audi expected poor sale values despite it's performance ! To this day the v6 tdi engine they still run at LeMans is still winning races with no real competition ! But what do i know ? I have a 300 Bhp smooth v6 diesel that can do 167 Mph and still returns 450 miles on a full tank which is £100 in uk ! I also happen to have a mapped s4 b6 (370Bhp) which does 150 miles on a full tank- also cost me £100- granted the diesel does not sounds the same as the v8 !
For your info they had plans to do the rs diesels for a few years now, however it's vauxhall/opel that took lead with their twin turbo models followed by Bmw with their x6 Md...if you ever get to take a ride in one- definitely will change your perception about the way diesels make power !
 
But where's the fun in having to change up at 4000? ;)

The later DSG/auto use 7 or even 8 gears so they keep the engine in the sweet spot where they produce max torque and power with less emissions ! It's however audi tradition to keep large v8 diesel engines for their limos, if they did a smaller a4 with a v8 diesel then you would not mind having to shift early ! Them engines are packing a phenomenal punch and their Bhp output only tell half the story, the max torque is at a measly 1500 rpm's all the way to 4500 which makes for a very, very smooth power graph so you don't get backlash ! Did i say they do map to over 400 Bhp with just a "generic" remap ? Add a pair of larger/hybrid turbo's and Bmw 535d injector tips and you'll frighten even the most "sports" cars on sale at the moment !
 
Personally not a diesel fan, however with 7 or 8 speed auto's I think they are weapons, I just like to rev!
 
Can anyone confirm this? Coming from Ford, which have the excellent, capless refuelling system called Easyfuel I had thought I'd quite miss it's ease

I've never needed to verify it... and I don't want to be the one at the petrol station who looks like he tried to put the wrong nozzle in his car! It just feels like the nozzle is going through some kind of mechanism when you put it in, that's all that made me think it.
 
you're going to get as many for as against petrol and diesel cars on here so you're just going to have to make up your own mind after having digested all the 'expert' opinion provided.
 
It's because of "purists" like yourselves that they did not do the r8 v12 tdi, audi expected poor sale values despite it's performance ! To this day the v6 tdi engine they still run at LeMans is still winning races with no real competition ! But what do i know ? I have a 300 Bhp smooth v6 diesel that can do 167 Mph and still returns 450 miles on a full tank which is £100 in uk ! I also happen to have a mapped s4 b6 (370Bhp) which does 150 miles on a full tank- also cost me £100- granted the diesel does not sounds the same as the v8 !
For your info they had plans to do the rs diesels for a few years now, however it's vauxhall/opel that took lead with their twin turbo models followed by Bmw with their x6 Md...if you ever get to take a ride in one- definitely will change your perception about the way diesels make power !

I find this a very interesting point you raise. I drive both a 3.0tdi in an A5 format and my S3, both have similar economy when (town driving only) as you mentioned £100 = 450 miles in the 3.0TDI and £65 = 320 miles in the 2.0T so for £100 they are pretty much even. The performance in the S3 is better IMO of course. The diesel is smoother but sounds like a tractor. The petrol sounds better especially pushing it right through the rev range, which it loves to do I may add. So really it does come down to personal preference and what is more desirable to you, some people love the low end torque of a diesel while others love the sound and ability to use the entire rev range. I don't think that we will see many diesels feature in RS/S cars as you say they would more than likely lose sales even if performance was still supercar performance.

However I am led to believe that the new BiTDI's are phenomenal engines, but as mentioned above I don't think they will ever make it to the RS/S.

Now saying that OP - if there was a choice between a similarly matched diesel and petrol engine, with the same torque coming in around the 2K rpm IMO I don't see the justification for the higher list price and higher pump price of a diesel (unless huge mileage is being done) especially with modern petrol engines becoming more and more efficient. This is comparing DSG vs DSG and manual vs manual. That's not saying diesels aren't good engines as I loved mine when I had it as it simply munched the miles and returned very good economy. I always find this debate an interesting one as everyone has their own personal opinion. Neither right or wrong. Just interesting to see all the different points for people supporting their chosen engine.
 
I've never needed to verify it... and I don't want to be the one at the petrol station who looks like he tried to put the wrong nozzle in his car! It just feels like the nozzle is going through some kind of mechanism when you put it in, that's all that made me think it.

Just verified it at lunchtime today after a quick look around to make sure noone was watching!

I looked in and there is a gate which I couldn't push open with my finger, so thought it must be there, but after I had filled up I tried putting a petrol nozzle in, and it won't go. Whether the fuel will get in if you then started trying to fill up I don't know, because it looks like there could be some gaps around it, but you'd soon realise either way I imagine!
 
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Just verified it at lunchtime today after a quick look around to make sure noone was watching!

I looked in and there is a gate which I couldn't push open with my finger, so thought it must be there, but after I had filled up I tried putting a petrol nozzle in, and it won't go. Whether the fuel will get in if you then started trying to fill up I don't know, because it looks like there could be some gaps around it, but you'd soon realise either way I imagine!

Even if there are gaps you wouldn't get much through them and the petrol splashing down the side of the car would be a dead give away.

On the S/RS thing - one other reason petrols are favoured is because they are lighter which makes balancing the car easier on front-engined cars; having a lot of weight over the front axle is less than ideal. Not to mention a lighter car is faster for the same power.

I think the high torque of powerful diesels becomes a problem too - building a clutch that can actually handle enough torque adds yet more weight to the car.