36 minutes ago, orangecurry said:

making a statement such as 'Tesco 99 is 0% ethanol' when even Tesco make no claims as such.

I don't think they're allowed to

I believe the "E5" labelling regulation is "up to" 5%

1 hour ago, DaveT70 said:

I believe the "E5" labelling regulation is "up to" 5%

I think so. Tesco just say this about Momentum in their FAQ's:

"Our Momentum 99 petrol contains a special blend of additives to help keep a car's fuel system clean and working at its best.

Additionally, the higher octane level (99 compared to 95 for regular unleaded petrol) gives improved overall engine performance for cars that are able to take advantage of this (generally, sportier models).

Most Tesco Petrol Filling Stations across England, Scotland and Wales stock Momentum 99. We don’t currently have a supply terminal that is able to produce our high octane base fuel to blend with our exclusive additives in Northern Ireland."

 

I do wonder whether they'd refer to the ethanol content anyway for the benefit of "normal" customers, rather than those of us who inhabit car forums!😀

 

3 hours ago, DaveT70 said:

I don't think they're allowed to

I believe the "E5" labelling regulation is "up to" 5%

These companies are certainly allowed to - you are correct in that the labeling on every pump has to be the same, but until a few years ago, ESSO marketed their RON 99 as 0% ethanol.

As I said, they dropped this marketing angle and it's no longer on their website.

https://www.wheels-alive.co.uk/esso-launches-synergy-supreme-99-premium-petrol-and-its-ethanol-free-at-the-moment/

From Esso  in 2021:
Although our pumps have E5 labels on them, our Synergy Supreme⁺ 99 is actually ethanol free (except, due to technical supply reasons, in Devon, Cornwall, North Wales, North England and Scotland). Legislation requires us to place these E5 labels on pumps that dispense unleaded petrol with ‘up to 5% ethanol’, including those that contain no ethanol, which is why we display them on our Synergy Supreme⁺ 99 pumps.

There’s currently no requirement for renewable fuel, like ethanol, to be present in super unleaded petrol although this could change in the future, in which case we would comply with any new legislation.”

..and here they withdrew the marketing..... this does not mean that ESSO 99 has ethanol in it for certain; only that ESSO no longer want to market it as such.

“We currently supply an ethanol-free Synergy Supreme+ 99 unleaded in some parts of the UK. From September 2023 our Synergy Supreme+ 99 will transition to contain up to a maximum of 5% ethanol at all Esso pumps irrespective of which part of the country they are located. The labelling at our pumps will remain as E5 for Synergy Supreme+ 99 unleaded."

I'm 'going on' about this as it is important to pass on facts rather than sweeping statements.  So AFAIK Tescos 99 and Shell 99 and ESSO 99 were NOT ethanol-free if supplied in the north of the UK, but they were in the south.

That may have changed for Tesco since 2023.  If exact ethanol content is important to you, do your own testing as above.

5 hours ago, Eric Bloodaxe said:

Yes, it serves you well, John!😀 

That was really the only time I found a particularly noticeable change between fuels. I switched to diesel a few years later, but the petrol cars we had then (Cavalier 2.0GLi and Astra 1.8 SRi) didn't like it one bit!

Vauxhalls at the time had a reversible plug under the bonnet to supposedly tweak the ignition timing to suit the lower octane rating of unleaded. I tried to do the right thing for a couple of weeks but soon reverted to lovely leaded 4* which was still available for some time and normality was restored!

Eventually higher octane unleaded was introduced, of course.

How old were the cavalier and astra. My a reg cavalier1.8 Sri and e reg astra2.0 gte ran fine on any grade. 

23 hours ago, alexp999 said:

I tend to put Sainsbury's 97 in mine, simply because it's the cheapest 97+ in my area. 

I could never get away with Sainsbury's super unleaded.  A full tank never seemed to cover the same distance compared to a full tank of Shell V-Power.

5 hours ago, iantt said:

How old were the cavalier and astra. My a reg cavalier1.8 Sri and e reg astra2.0 gte ran fine on any grade. 

G and E prefix  respectively. Sounds like individual cars differed then. They were both standard, btw. Mate of mine had a 2.0i GTE around the same time (lease car, so also unmodded) and that wasn't too happy either.

 

12 hours ago, mickywrx said:

I could never get away with Sainsbury's super unleaded.  A full tank never seemed to cover the same distance compared to a full tank of Shell V-Power.

Yes I found Sainsbury's Super to be poor too

Strangely I found Sainsburys diesel was more sooty than BP diesel, creating more mess on the boot of non-DPF cars and creating more regens on cars with a DPF.  Both regular, both within a mile or so and both offered Nectar points at the time I was testing.  I genuinely expected them to be the same with maybe just a slight change in additives, but was proven wrong through testing.

3 minutes ago, TomsFocus said:

Strangely I found Sainsburys diesel was more sooty than BP diesel, creating more mess on the boot of non-DPF cars and creating more regens on cars with a DPF.  Both regular, both within a mile or so and both offered Nectar points at the time I was testing.  I genuinely expected them to be the same with maybe just a slight change in additives, but was proven wrong through testing.

Yes, the Diesel is poor too.

Average MPG drops by 5MPG on that and it's as flat as flatulence too