Cheapest eg asda then twice a year run 1 bottle of millers eco diesel through it.

In my old mkI Octavia I used Millers for about 6 months with supermarket diesel, it made no appreciable difference to fuel consumption.

 

I generally fill up with supermarket diesel but also sometimes use Shell/BP etc.  Based on my records any difference in consumption due to fuel source is completely drowned out by driving style and driving conditions.

Works derv will run on anything but really well on Sainsbury's city diesel for running and mpg.

Our Touran hates Tesco and shell and runs like a bag of nails on either. It's not bad on Sainsbury's, but prefers BP standard diesel for running and mpg.

Our petrol cars equally had a mix. Mk1 20v elegance liked Total best, mk 2 loved Tesco best.

what a load of *******s haha, I couldn't help but laugh at that when you are arguing that the fuels are all the same and none of them make a difference but now your saying your car hates one or the other? Good god.

what a load of *******s haha, I couldn't help but laugh at that when you are arguing that the fuels are all the same and none of them make a difference but now your saying your car hates one or the other? Good god.

And what fuels and results do YOU get, or do you simply fill up with v power?

I'd do some testing of fuels yourself and I'm certain you'd be surprised at the results

And what fuels and results do YOU get, or do you simply fill up with v power?

I'd do some testing of fuels yourself and I'm certain you'd be surprised at the results

I think his point was that you've massively contradicted yourself more than anything.

I must say that in well over 300k of driving I have never had a problem with fuel, except when a colleague filled a ducato van to the brim with petrol.

You may get a visit from the RFTU if you are unlucky and they can take the car as well. In Holland it has a green marker.

I know. It was a joke.

I think his point was that you've massively contradicted yourself more than anything.

On which bit?

.

I completley agree - everyone is entitled to a preference and has the right to express that preference.

However that is rather different from simply announcing that something is "a definite fact", without offering any evidence.

Well we agree on something at least. As I said earlier you are convinced that there is no difference so no matter what proof I posted here you would deny that it was proof, so let's just drop the debate here and now, I'm bored with it and have far better things to do with my time.

All I will say to end my contribution to the debate is this, in my own tests driving in the same way on my daily commute and other identical journeys the following cars have delivered significantly better economy on branded fuels than in supermarket : BMW 328i Touring auto, BMW 123d manual, Honda Civic 2.2 diesel ( the horrible futuristic shaped one, 2005 m.y.), Honda Jazz CVT auto, 2005 and 2011 m.y. , Honda S2000, Porsche Boxster x2), Porsche Cayman s PDK, Porsche Carrera C2S PDK, Toyota Yaris D4D.

As mentioned earlier I have not used supermarket fuel in my Octavia to date.

Edited 17 November, 201312 yr by Timoctav

Wow, this is a very long thread for what really is a non-issue and which has been debated so many times before. At most it will (potentially) make a difference of a couple of quid here and there, is that really worth the aggravation?

In fairness to Timoctav, none of the cars in that list have particularly sophisticated engines so that may have contributed to the impression that fuel quality makes a difference in mpg.

Now I better go, things are really heating up in the Supermarket vs Branded Air thread.

I know. It was a joke.

 

Having seized people cars in the past for similar excise offences it is surprising how people think that cheating on a few quid of excise duty can result in the seizure of their car.  I usually restored the car to them for a percentage fee of the Glasses value of the car as it was always such a pain taking it to storage, awaiting appeal against seizure and then disposal of it through the Queen's Warehouse along with the other cars, truck, boats, aircraft seized for other nefarious purposes, that is as long as the Investigation Service did not fancy it for their ops work.     

And what fuels and results do YOU get, or do you simply fill up with v power?

I'd do some testing of fuels yourself and I'm certain you'd be surprised at the results

always have and always fill up with V-power, don't care about what difference it makes, just my choice.

Wow thanks for the replies...  Clearly, you're all too tight the expensive stuff, but not tight enough for supermarket fuel!!!

 

It seems that it has less of an impact than petrol, which isn't much.  I avoid supermarket petrol like the plague - no particular reason, I just don't think Sainsburies or Tescos have any business being anywhere near my car....

For diesel you can generally use anything and not notice a real difference. If however your car takes a dislike to one fuel, feel free to pick and choose.

 

For petrol things differ, especially with performance and turbo engines. Most modern cars "learn the limits of their fuel" and will retard the ignition if they sense knock (reduce power to prolong life). The major contibuter towards knock is low quality (RON) fuel. Within the EU standard unleaded is set at a reasonable 95 RON. Within South Africa standard unleaded is 93 RON (poor), whilst in the USA it is 91 RON (dishwater). Japanese standard used to be 100 RON (fantastic) and may still be the case. The higher the RON, the better the performance, but this doesn't mean to say that cars will not run on low RON. VW sells the Golf GTI in the USA and works fine on 91 RON, although it probably produces 10-20BHP less power.

 

My old Subaru (Jap Import) ran like a dog unless it was fed Super Unleaded (99 RON at the time) with Octane booster. This is because it was designed for a market where 100 RON was the minimun. All oil companies do to boost Octane levels is add ethanol to the mix. It prevents the fuel from pre/self-igniting at higher temperatures, preventing knock.

 

Diesel is a much more robust/tolerant fuel. 

Edited 18 November, 201312 yr by Orville

whilst in the USA it is 91 RON (dishwater)

Thats not quite true, the US report the average of the RON and MON figures which tend to differ by about 10 (MON being the lower). As such US gasoline actually has a RON approaching 95.

According to Wikipedia (what do they know??) Australia, New Zealand, Canada and the US have a "regular" rating of 91-92 RON (82-83 MON).

 

Exxon Mobile's US website states the following; "Gasolines are rated based on octane. In most areas of the country our regular gasoline is 87 octane, midgrade is 89 and premium is 91 – 93. If you check your owner’s manual, you’ll find the recommended level for your engine." Link here.

 

The US uses the AKI rating, which does indeed sit in the middle of RON and MON values.

87 AKI = 91.6 RON (Regular)

89 AKI = 94 RON (Midgrade)

91-93 AKI = 96-98 RON  (Premium/Super)

 

US Regular is quite a bit inferior to EU Regular. US midgrade comes close to EU Regular, and US Premium sits between our Regular and Super. Put simply, we get better fuel but we pay more than twice as much for it after the TAX man has taken his cut.

 

edit: ...but OP is talking diesel which requires much greater temperatures before it self-ignites, so RON/MON/AKI matters not a jot in his case.

Edited 19 November, 201312 yr by Orville

Quite correct, now we are talking about Cetane Number or Index, depending on how you determine it.

Jet fuel is so mush easier

Hi Matt

If you get better mpg on Shell tell everyone. if you don't just tell me..... :-) ( No smilies available on iPad for some reason). To be honest I think the difference between thee and me is I'm up and out at 06:00hrs every morning before there is a lot of traffic about and my daily commute is mainly steady speed open roads. The motorway ends literally a couple of hundred metres from the security gate where I work.

My fuel consumption is not so good now the colder weather has arrived, but I don't bother checking it every time, the novelty has worn off!!

First brim to brim with Shell and gained 4.3 mpg over previous fill up! Early days in my long term test, but it appears that mine likes Shell after all!

I can't comment on mpg but my old 3 series coupe (E46) would run soo much better when I filled up with standard Shell.

I thought it was just me but I picked my partner up from the station after I filled up with Shell without her knowing and she commented how much smoother the car was.

 

My old diesel Passat (soon to be replaced by a vRS) couldn't give a flying toss what brand of fuel I use.