Audi A6 Diesel S Tronic - Best Fuel?

[Suri66]

Hi. I have a Audi A6 C7 2.0 diesel S Tronic and wanted to gauge peoples real life use of fuel. Owned car 6 months now and pretty much used Shell V-Power Diesel whole time. Not tried any other and currently getting these figs approx

£20 - 100 miles town driving.

Iv read BP is quiet good along with BP Ultimate but thats just with an extra additive hence the price of ultimate. Any others i could look at the will look after my car and maybe get a little bit more mpg out of it?

Any help would be gratefully appreciated.

[beemerboy9]

I have been advised by a VW Audi independent garage to use nothing but V-Power. I am doing this even though my car only gets used for longer journeys (I am lucky to have the use of a petrol-engined run-around as well)

What the guys who write into the forums complaining about sooted-up EGRs and DPFs never tell us is which fuel has been used.

[Gazwould]

Please tell me the Cetane number of BP Ultimate and Shell V-Power derv .

[Whippy53]

Best thing to use is Lidl fuel with a healthy dollop of chainsaw oil. Last forever.

[Gazwould]

No snake oil is supreme .

[Roverfan]

I only use supermarket fuel been driving the precarious cayc crtdi last 5 years and no probs, neither on the pug 207 hdi previous 5 years.
In terms of causing problems it's certainly a myth. In fact I stay away from shell/BP because fancy stuff is more likely to have bad batches

[KevTrem]

I personally use Costco diesel, averaging 560miles to a tank general running around and commute. 400miles to a tank when towing and 700 miles to a tank solely motorway miles. I've tried V-Power diesel, no different in MPG, noise or power from regular diesel. Supermarket Diesel I feel makes the engine noisier and slightly less MPG, found this on my current Allroad, my previous Avant and my Peugeot 407 2.0HDi (136) before the Audi's.

[robes401]

I have owned my A6 S-line Avant S-tronic Ultra since new in September 2014, and had periods of using shell v-power exclusively, and periods where I have used standard (mostly shell fuelsave) fuel.
Here are my results (I record my mileage and fill-up amounts at every trip to the pumps):

V-power fuel (91 fill-ups): 51264 miles travelled on 5176.2 litres of fuel with an mpg of 45.0
Standard fuel (113 fill-ups): 68494 miles travelled on 7032.5 litres of fuel wiht an mpg of 44.3

I would say that taking into account the uncertainty associated with the reuslts (e.g. different length journeys, ambient tempteratures etc.) this results in a negligible real world difference in fuel economy between v-power and standard fuel.

[Elansear]

Diesel in the UK conforms to, BS EN590. There is no other standard for diesel with additional products whin it, so wherever you get it the supermarket or a branded garage it all starts out the same. Manufacturers build their vehicles to use fuel to this standard and to conform to any environmental measures in the UK. So any claims that a product is better than another because it has X Y or Z has to be speculation as they all have the same standard to meet. I have only used supermarket fuel with the exception of filling up when on holiday etc for over 15 years in various makes of car and never experienced any issues. As somebody has mentioned the additional products over the standard could cause issues as everything is designed around the standard.

[danclyon]

I have owned my A6 S-line Avant S-tronic Ultra since new in September 2014, and had periods of using shell v-power exclusively, and periods where I have used standard (mostly shell fuelsave) fuel.
Here are my results (I record my mileage and fill-up amounts at every trip to the pumps):

V-power fuel (91 fill-ups): 51264 miles travelled on 5176.2 litres of fuel with an mpg of 45.0
Standard fuel (113 fill-ups): 68494 miles travelled on 7032.5 litres of fuel wiht an mpg of 44.3

I would say that taking into account the uncertainty associated with the reuslts (e.g. different length journeys, ambient tempteratures etc.) this results in a negligible real world difference in fuel economy between v-power and standard fuel.


Last 40k miles I've done 20k on Tesco diesel, and 20k on Shell Fuelsave diesel. I get about the same as you when using the supermarket diesel, but just under 50 (49.3) long-term as measured by the car.
On a tank-to-tank comparison (brim to brim) over the same period, the Shell seems to give me about ~50 miles more per tank - driven in the same way, on the same roads across the same 1 year period (pre-lockdown).
I will say the "sound" of the engine is very different on different diesels, so the additive package clearly makes a big difference (for instance on Sainsburys or Morissons diesel I might as well be driving a 2004 transit it sounds that clattery). Pretty much everything else seems to "sound about the same". I used the original vPower (which was a GTL fuel) in my last A4 and it was a revelation - but it was expensive at the time. Trials with the current vPower seem to suggest no meaningful change in engine sound or economy (maybe a tiny bit but 0.3mpg or something like that). Pretty much it's 750 miles on a tank of supermarket fuel, and 800+ on Shell (best is 870 miles on one full tank when a lot of the journey was an enforced 50mph).

HTH,
Dan.

[beemerboy9]

Last 40k miles I've done 20k on Tesco diesel, and 20k on Shell Fuelsave diesel. I get about the same as you when using the supermarket diesel, but just under 50 (49.3) long-term as measured by the car.
On a tank-to-tank comparison (brim to brim) over the same period, the Shell seems to give me about ~50 miles more per tank - driven in the same way, on the same roads across the same 1 year period (pre-lockdown).
I will say the "sound" of the engine is very different on different diesels, so the additive package clearly makes a big difference (for instance on Sainsburys or Morissons diesel I might as well be driving a 2004 transit it sounds that clattery). Pretty much everything else seems to "sound about the same". I used the original vPower (which was a GTL fuel) in my last A4 and it was a revelation - but it was expensive at the time. Trials with the current vPower seem to suggest no meaningful change in engine sound or economy (maybe a tiny bit but 0.3mpg or something like that). Pretty much it's 750 miles on a tank of supermarket fuel, and 800+ on Shell (best is 870 miles on one full tank when a lot of the journey was an enforced 50mph).

HTH,
Dan.

I ma not so interested in fuel economy. Since I have been recommended Shell V-Power, I really want to know whether the inside of the engine, EGR cooler, turbo inlet vanes and DPF are cleaner when using premium fuel.

[danclyon]

I have been advised by a VW Audi independent garage to use nothing but V-Power. I am doing this even though my car only gets used for longer journeys (I am lucky to have the use of a petrol-engined run-around as well)

What the guys who write into the forums complaining about sooted-up EGRs and DPFs never tell us is which fuel has been used.

I've (last 5k miles) just had a new EGR cooler as it was clogged up - but according to Audi it is nothing to do with the fuel, it's to do with the driving style (which I find hard to believe as the Ultra does love a good right foot booting and it gets it). The previous owner judging from the miles covered and the tyres consumed must have been an incredibly spirited driver meaning I did 20k on supermarket fuel and actually nearly 30k now on Shell Fuelsave.....the EGR cooler got blocked because of the reagent contaminating it not soot.

If you read, say, the shell website (they seem to be the most ready with their info) they do claim a cleaning effect but only of the combustion chamber (valves, cylinder head etc.) and show before and after shots after so many miles. They also quote (heavy fleet) maintenance improvement etc., over the previous "standard" fuels, economy improvements and cleaner emissions, but it's global data, and forumlations change between regions owing to the composition of the base fuel etc. so really hard to judge what is real.

In short, clean, lean burn and everything working correctly, constant speed and temperature and then there shouldn't be an issue, but no car undergoes that duty cycle.

Personally I rely on a bottle of Liqui Moly every 5-10k miles (and definintely about 500 miles before it goes for service) to clean as much of the crap out of the system as possible.
Certainly on the last car (no DPF mind) the EGR cooler failed before 25k miles (A4 1.9TDi 130 PD), but once that was replaced it ran through 250k miles with 200k of them on supermarket fuel and never had any problems again (if that's any form of indicator at all).

Personally, I'd stick to Shell Fuelsave diesel and a bottle of Liqui Moly every 10k miles vs the current gen VPower - as I say, since they took the GTL out and did it all with additives only, it just hasn't had the same "feel" to it - subjective I know but that's my 2 cents.

D.

[beemerboy9]

I've (last 5k miles) just had a new EGR cooler as it was clogged up - but according to Audi it is nothing to do with the fuel, it's to do with the driving style (which I find hard to believe as the Ultra does love a good right foot booting and it gets it). The previous owner judging from the miles covered and the tyres consumed must have been an incredibly spirited driver meaning I did 20k on supermarket fuel and actually nearly 30k now on Shell Fuelsave.....the EGR cooler got blocked because of the reagent contaminating it not soot.

If you read, say, the shell website (they seem to be the most ready with their info) they do claim a cleaning effect but only of the combustion chamber (valves, cylinder head etc.) and show before and after shots after so many miles. They also quote (heavy fleet) maintenance improvement etc., over the previous "standard" fuels, economy improvements and cleaner emissions, but it's global data, and forumlations change between regions owing to the composition of the base fuel etc. so really hard to judge what is real.

In short, clean, lean burn and everything working correctly, constant speed and temperature and then there shouldn't be an issue, but no car undergoes that duty cycle.

Personally I rely on a bottle of Liqui Moly every 5-10k miles (and definintely about 500 miles before it goes for service) to clean as much of the crap out of the system as possible.
Certainly on the last car (no DPF mind) the EGR cooler failed before 25k miles (A4 1.9TDi 130 PD), but once that was replaced it ran through 250k miles with 200k of them on supermarket fuel and never had any problems again (if that's any form of indicator at all).

Personally, I'd stick to Shell Fuelsave diesel and a bottle of Liqui Moly every 10k miles vs the current gen VPower - as I say, since they took the GTL out and did it all with additives only, it just hasn't had the same "feel" to it - subjective I know but that's my 2 cents.

D.

So a reagent in Shell Fuelsave eventually resulted in the EGR becoming blocked and this was not helped by the duty cycle created by your usage of the car.

If you changed fuel would that have helped - according to Audi? Or would the way you use the car (short journeys?) cause the blockage irrespective of fuel?

A lot of questions, I know?

[danclyon]

So a reagent in Shell Fuelsave eventually resulted in the EGR becoming blocked and this was not helped by the duty cycle created by your usage of the car.

If you changed fuel would that have helped - according to Audi? Or would the way you use the car (short journeys?) cause the blockage irrespective of fuel?

A lot of questions, I know?

No the reagent is the adblue - it somehow "contaminates" the EGR cooler - it's a known problem and there's an audi TSB on it, it even blames "driving style" - which I find hard to believe personally.....the fuel doesn't play a part in it at all.

Cheers,
Dan.

[beemerboy9]

Hi Dan, thanks for the clarification. Mine is not an Adblue car. Bad news:- I'm a Londoner with a non-ULEZ car :1zhelp:- good news: no Adblue :Blush:.

[OVI82]

Although I’m no expert in fuels and what exactly goes in them I will say that I’ve only ever used Shell V Power in all the Audis I’ve owned.Since 2008 I’ve not used anything else other than shell V Power.Not used BP ultimate or Tesco 99 or whatever else is called.
Owned the BITDI for 18 months,the A6 C6 3.0 Tdi before it for 6 years and the A4 before that for another 4 years have only ever had Shell V power.I don’t use anything else and I have never had an issue with EGRs,DPFs and so on.And most of my driving is in London with a LOT of stop-start.Again never had an issue.The way i see it,what’s the point in spending anywhere between £10000-£50000 on a car only to try and save a few pennies on a tank full.For me personally it’s an obvious choice.

[Gazwould]

It's so much cheaper to boost the Cetane number yourself.

[Whippy53]

It's so much cheaper to boost the Cetane number yourself.

Yup, I regularly tip a couple of shots of Stolichnaya in the tank. Works wonders. Remember kids, don't drink and drive.

[Scott K]

I would think the main killer of modern engines is the long life oil changes. I change my oil and filter every 6 months or 10k miles so hopefully that helps. I'm also lucky that the bulk of my driving is longer journeys.

[Gazwould]

LongLife intervals are loony , the actual oil though is superior.

[lynalldiscovery]

I think all the VAG 4 pots sound dog rough on a good day, all the 6 pots sound lovely, as for fuel stick in whatever no one really cares.

[dervdave]

I use nothing else but the best diesel you can buy Shell V-Power :biggthump

[OmegaV6]

Nice if you can get it .. nearest V-power shell station is 18 miles away ... am I REALLY going to do 36 miles just for some fancy fuel ??? ........

[Gazwould]

It's really worth it !!


https://youtu.be/5fKxLOTVEnI

[Bishop187]

Fifth Gear - series 15 episode 4, premium diesel test - YouTube (https://youtu.be/ezjknhwcQXU)


Sent from my iPhone using Tapatalk

[dervdave]

Nice if you can get it .. nearest V-power shell station is 18 miles away ... am I REALLY going to do 36 miles just for some fancy fuel ??? ........

Yep a nice little run out that will also give your DPF a chance to regen :D

[OmegaV6]

Yep a nice little run out that will also give your DPF a chance to regen :D

Not a chance !! Of the 18 miles about 10 are 30mph, a couple are 40 mph, about a mile of 50mph, and the rest is 60mph .... no way will a dpf regen occur under those conditions.

A far more effective, cheaper and less time consuming method is the use of Hydra Maximus ... about £4 per tank of diesel, which is less than the fuel wasted driving to get V-power ......

Hydra MAXIMUS Best Diesel Injector Cleaner Improves Fuel (hydra-int.com) (https://www.hydra-int.com/maximus-diesel-power-booster.html)

[danclyon]

It's really worth it !!


https://youtu.be/5fKxLOTVEnI

Brilliant video - absolutely brilliant!