Which. Supermarket petrol quality: what you need to know

[Marlinleg]

I thought this may be f interest to members.

 

https://www.which.co.uk/reviews/new-and-used-cars/article/supermarket-petrol-quality-what-you-need-to-know-aWlmN3O20LKI

 

[Bluemarlin]

I find that it comes down to personal experience/preference.  

I recently found that Sainsburys E10 got me around 25-27 mpg, compared to Tesco/Costco/Shell E5 giving around 30mpg. Esso E5 gets me upwards of 31 mpg, with the current tankful averaging around 35 mpg.

[Mr Vlad]

I can't remember the last time I used a 'normal ' petrol station. I've been using either Asda or Tesco as I've one of each within 1 mile of where I live. 

I'd say most folk use a supermarket for fuel for economic reasons. Running a car is getting more expensive year on year so folk just find the cheapest fuel they can. 

[Gary H]

It certainly is of interest. Many thanks for the link.  

From my experience in the UX, it’s economy has suffered by using E10 over E5, but in a slightly unusual way which I’m not sure if any fellow members could relate to. If I'm just pottering around town or going back and forth to work – the difference is minimal. However, on distance runs it does seem to drop it by a good 4-6mpg compared to what I used to be getting from E5. For instance, on one particular drive I do (roughly 250 miles), I used to get around 56-58mpg, depending on how I drove. Today? Using the same route, I struggle to get much more than 52/53mpg. I have to almost 'hypermile' to get it close to those old figures. 

I have similar kinds of results if I compare supermarket fuel to branded fuel. Again, on the same route I've compared figures by using supermarket fuel on the way down and then branded fuel on the return leg the following day. I generally get a few mpg more from branded fuel and that's also noticeable on the fuel gauge at the end of the journey.

[Marlinleg]

We're I fuel Shell £145.99p unleaded Tesco £137.99p unleaded and they are 2 mile apart 

[wharfhouse]

My take on this is:

I have used supermarket fuels for decades and run cars to high mileages without any problems. 

I found a noticeable drop in economy using the new E10 (over the old spec 95 octane fuel) - strangely not immediately but after a number of months. 

I switched to the new E5 instead of E10 and the economy went back to previous (or slightly better) levels making the same trips in the same conditions comparing the same supermarket E5 and E10 (in this case the same Sainsbury's). 

The difference between E10 and E5 fuel economy is between 5% and 10% - I find if E10 is in the tank for some time (a few weeks) the economy definately falls off which doesn't happen with E5. 

As for performance I can't really tell the difference between E5 and E10 but the car does run noticeably quieter and smoother on E5 - again this is comparing E10 and E5 from the same Sainsbury's. 

My conclusion from the above was if there is less than 10p (at today's prices) difference between E10 and E5 then using E5 will break even or save me money (and the car seems to run better on E5). Now, Sainsbury's used to be about 6p difference per litre between E10 and E5 (so definitely saving me money) but more recently I noticed the difference has crept up to 10p a litre. 

I've tried various branded E10 and have not noticed a significant change over the supermarket fuel - for me BP E10 seemed to offer a small improvement, Shell E10 not (in fact I thought it was slightly worse) and so overall I do make a saving using supermarket fuel given the extra cost of branded fuel. The E5 price difference for branded fuels I've tried (which is often more than 10p a litre) could never be more financially economical. 

About 6 months ago we got a Costco fuel station near to me and so I switched to Costco for the majority of my fuel. The fuel is always a few pence per litre cheaper than even the cheapest supermarket alternative - sometime more - and the difference between their own E5 and E10 is about 7p per litre. So I now use Costco E5 wherever I can. The car runs very quietly and smoothly on this and compared to any branded E5 (BP, Shell etc.) the price difference is some 20p a litre cheaper so a no brainer really. 

 

[Sundance]

An interesting article Phillip, thanks for posting.

I'm a mix 'n' match kinda guy, currently experimenting with half a tank of Esso E5 plus half a tank of Sainsbury's E10.

I guess you'd call it a sort of E7.5 with some measure of detergent and friction modifier thrown in 😉 .

Cost averages out at around £1.40pL as I collect Nectar pts at Sainsbury's then spend them @ Esso who discount fuel by 5ppL 👌 .

[Marlinleg]

Wharfhouse  thank you I have posted this on the Toyota forum with credit to you . Thanks again I am going to follow your advice once I get my fuel lower I have half a tank 

[Mr Vlad]

Interesting Phil. Did you not have to join Costco before you started fuelling up there?

Strange how in your E10 compatible car you find it's fuel consumption is poorer using E10 compared to E5. My not compatible E10 car gives better fuel but I use an additive to counteract the effects of the ethanol. 

 

[wharfhouse]

3 hours ago, Mr Vlad said:

Interesting Phil. Did you not have to join Costco before you started fuelling up there?

Strange how in your E10 compatible car you find it's fuel consumption is poorer using E10 compared to E5. My not compatible E10 car gives better fuel but I use an additive to counteract the effects of the ethanol. 

 

Yes you have to be a Costco member to get petrol there. On the E10 vs E5 when the new E10 first came out my petrol consumption was better but after a few months then got worse than when on the old 95 and that's when I started experimenting. 

[Linas.P]

I personally have not noticed the difference between "branded" vs. supermarket, or for that matter regular vs. "premium". Sometimes there are some batches that are better or worse, sometimes I could even feel like car is not pulling the same, sometimes it is better. I have got bad batches of fuel both from supermarket and from big brands, I have even good bad batches of "premium/super/duper/mega/100 Octane" fuels. Now the argument may be that "branded" fuels are more consistent, but I found that not to be true - most consistent fuel is in the busiest petrol stations, the more they sell, the more they order, the fresher is the fuel and it is more consistently good. The smaller and the quieter petrol station is, the less consistent is the fuel - if they just got delivery and you getting fresh fuel it may run better, but if it was sitting in the underground tank for a month it may be not as good. And that means that in my experience I get more consistently good fuel from supermarket where there is living queue 24/7, then buying some mega expensive 100 Octane fuel from some small petrol station where nobody ever buys it and where that "premium" fuel sits longer. As a matter of fact the best mileage I get is usually from the worst fuel I buy in ASDA... I assume that has something to do with IS250 having "smart" ECU which adjust for the fuel, so it is possible that ECU just retards the timing for worse fuel and as result makes engine actually more economical, but less powerful... whereas worse economy was always the premium fuel, again perhaps because it gives more power, but less economy. Now this was true when 95 was petrol and not half vodka, sadly E10 is always going to be worse for economy, because it contains literally less fuel in 1L than pure petrol did. Still in my experience the difference is negligible ~1-2% maybe.

 

Now when it comes engine preservation and cleaning - this is mostly snake-oil, yes premium fuel may slow down the accumulation of some dirt in the engine... and yes it is lab proven that in ideal conditions running 2 engines exclusively on premium vs. regular petrol for 100k miles there will be differences. There will be slightly more warmish on the engine that was running regular, maybe slightly more visible carbon deposits, but in grand scheme of things it does not matter. Engines are not run in ideal conditions, nor they are ever run on exclusively one type of fuel, nor even the differences that are "proven" in laboratory makes up to anything meaningful. One honestly would need to run engine for several millions of miles before just the cleaning effect of the fuel would be the distinguishing factor between one engine which is failing and other one which doesn't. So perhaps better idea is to save £5 per tank and do oil change after 5k miles instead of 10k miles, because at least that will have quite meaningful positive effect on wear and tear, rather than buying magical additives which will make no difference in whatever 100k miles you will be driving.

On 4/25/2023 at 8:04 PM, Gary H said:

It certainly is of interest. Many thanks for the link.  

From my experience in the UX, it’s economy has suffered by using E10 over E5, but in a slightly unusual way which I’m not sure if any fellow members could relate to. If I'm just pottering around town or going back and forth to work – the difference is minimal. However, on distance runs it does seem to drop it by a good 4-6mpg compared to what I used to be getting from E5. For instance, on one particular drive I do (roughly 250 miles), I used to get around 56-58mpg, depending on how I drove. Today? Using the same route, I struggle to get much more than 52/53mpg. I have to almost 'hypermile' to get it close to those old figures. 

I have similar kinds of results if I compare supermarket fuel to branded fuel. Again, on the same route I've compared figures by using supermarket fuel on the way down and then branded fuel on the return leg the following day. I generally get a few mpg more from branded fuel and that's also noticeable on the fuel gauge at the end of the journey.

I am not sure if this is the reason why, but MPG is quite stupid measurement... it is alright for the range (or would be "alright" if we used gallons in UK, but we don't), but it is horrible for economy. So assuming that hypothetically E10 economy in your car is 10% worse, and that in the city you get 35MPG on E5, then on E10 you would get 32MPG - the difference of only 3MPG. Yet on the motorway where you are getting 58MPG on E5, the exactly same 10% will make 6MPG difference and you will get 52MPG. In short the higher is your MPG, the bigger the the "efficiency" gap will look. I maybe wrong, but I thought that could be one of the reasons - i.e. MPG is kind of misleading measurement.

[Jgtcracer]

I’m not sure if it’s just me but I seen to had recently noticed a bit of a drop in fuel economy using E10.  Ive got a suspicion that the ethanol content of fuel has recently crept up to closer 10%.  In gaining at least an extra 2mpg from the car having swapped back to V-power.  Doesn’t sound like much but it’s 10% in an RCF!

 Anyone else noticed anything recently?

[Mr_Groundhog]

I will share a quick anecdote: a friend who drives a Porsche 997 got an engine dash light on, and got scared. Took it to the Porsche specialist right away and the mechanic asked: "where did you last top-up fuel?" and he told him it was a low-cost gas station at a supermarket (those whitout humans at all)

The mechanic said not to worry and upon deactivating the alert, told him the remedy was a full top-up of Shell/BP E5 to flush it.

Apparently the petrol is the same but the filtering (purity) and the additives can make all the difference. He's got no more engine lights turn on since.

BTW I saw Halfrauds sell a bottle of an additive that claim to make E10 safer. Anybody knows? Im curious but ultimately, I only refuel 98/99 E5 anyway. The car seems to like it better.

[Las Palmas]

Cheap: gasoline 95 octane 1.07€ - diesel 1.10€

Shell super 98 octanes 1.39€, 95 octanes only .05€ cheaper. BP and the rest are all more or less same price.

So far, I have been filling Shell in as wonder why somebody can sell gasoline so much cheaper than all the other companies and when passing by one of the Petroprix stations there are only few cars filling there. Is the reason for few customers with Petroprix that everybody else are suspicious like I am?

[Mr Vlad]

Well Mr Groundhog. The E10 protectorate could be Millers EPS. I've been using it for a good few months now. Only use it when I fill up with E10. I don't notice a difference But because it's Millers and I trust them implicitly and been using their products for decades. I'm confident my fuel system components are out of harms way when using EPS.

[Marlinleg]

Uk Super-market 95 octane £1:44p

shell 95 octane £1:69p

[wharfhouse]

11 minutes ago, Marlinleg said:

Uk Super-market 95 octane £1:44p

shell 95 octane £1:69p

And you can usually get supermarket E5 cheaper than branded E10 - so the question then is which is better for the car -Supermarket E5 or branded E10? I know for sure (as I have tested it) that the supermarket E5 will give me better mpg than branded E10.

[Mr_Groundhog]

Just in case, I'm not letting my car anywhere near supermarket fuel and only give it BP or Shell 98/99 E5. Call me paranoid, but for the difference I'm not gonna take the long-term risk (I don't do lots of mileage anyway)

[Jgtcracer]

On 6/20/2023 at 3:18 PM, wharfhouse said:

And you can usually get supermarket E5 cheaper than branded E10 - so the question then is which is better for the car -Supermarket E5 or branded E10? I know for sure (as I have tested it) that the supermarket E5 will give me better mpg than branded E10.

I’m currently using Tesco 99Ron and must say, it’s performing quite well.  Have went from 22mpg to 24mpg and car seems to like it.  Watched a few YouTube videos recently interviewing car tuners in the UK who really like the stuff due to quality and consistency.  Was previously using Shell Vpower but it’s around 10p dearer where I live and do 10,000 miles a year.  Going to stick with it for a few months and see how it goes…..

[scudney]

Welcome to the club Marcus, been using Momentum 99 since the early 2000's 😊👍

[Rabbers]

I recall visiting the U.K. by car a few years ago, mainly the Surrey/Sussex area, and seeing warnings on TV about Tesco petrol after numerous customer reports of breakdowns due to clogged injectors.  Presumably the issue, which appeared quite serious, was satisfactorily resolved.  Not that it can have done Tesco’s reputation much good. 

[ColinBarber]

1 hour ago, Rabbers said:

I recall visiting the U.K. by car a few years ago, mainly the Surrey/Sussex area, and seeing warnings on TV about Tesco petrol after numerous customer reports of breakdowns due to clogged injectors.  Presumably the issue, which appeared quite serious, was satisfactorily resolved.  Not that it can have done Tesco’s reputation much good. 

That was a one off where diesel got mixed up with petrol. It happens very occasionally at an individual station, be that Tesco or any other retailer. 

[Malc1]

2 hours ago, Rabbers said:

Not that it can have done Tesco’s reputation much good. 

I'm not sure they care one jot  .......  it's just freebie publicity for them

and some of this theorising about specialty fuels with BP Shell etc  .  my local BP garage recently changed to Shell and with the change went the MFG logos on the carwashes 

I'm sure MFG provided that BP station with fuel  .  are MFG Morrisons maybe / Asda or which, I'm never sure these days ...........  !!!

Malc

[Rabbers]

4 hours ago, ColinBarber said:

That was a one off …

Glad to hear it, though I had the impression that several Tesco forecourts over a wide area were affected, implying a mishap at the refining or distribution levels.  

[Illogan]

6 hours ago, Malc1 said:

I'm not sure they care one jot  .......  it's just freebie publicity for them

and some of this theorising about specialty fuels with BP Shell etc  .  my local BP garage recently changed to Shell and with the change went the MFG logos on the carwashes 

I'm sure MFG provided that BP station with fuel  .  are MFG Morrisons maybe / Asda or which, I'm never sure these days ...........  !!!

Malc

https://en.wikipedia.org/wiki/Motor_Fuel_Group