What fuel ?

NLW73 · 12 May 2025

I try and use injector cleaner every 6 months. it's supposed to work. more placebo too

Tesco is just down the road from me which is 99. Shell V power just around the corner too.

Marty* · 12 May 2025

I just use Momentum 99 in mine and so far so good

Alex · 12 May 2025

My mechanic always told me to wack a bottle of redex/injection cleaner in every now and again. He always told me to put the full bottle in with a full tank if you want it to do anything (ignore what it says on the bottle). Tesco every few months sell redex at half price for clubcarders, so when it's on offer I usually add a bottle.

Sunnyspells · 12 May 2025

I use petrol treatment from Forte. I remember it was added at each service from the OPC for my 968. As I've just got this car I've used a bottle on my last fill.

Artic987S · 15 May 2025

Sunnyspells said:
I use petrol treatment from Forte. I remember it was added at each service from the OPC for my 968. As I've just got this car I've used a bottle on my last fill.

Is it a 98 R plate?

Sunnyspells · 15 May 2025

it is a 99 V plate.

The Baron3 · 17 May 2025

Any 99ron, mainly esso or shell

Marko1982 · 17 May 2025

I always use Tesco 99 whenever possible, massively cheaper than other super unleaded fuels and having come to the 996 from a tuned Focus ST, always stood up really well to knock resistance under boost.

Whilst the application in this video is a 2.0 turbo, it shows how well it stands up where there is probably more stress on the engine than a large capacity naturally aspirated engine as in the 996:

gizlaroc · 17 May 2025

sleevie said:
I'm using Esso Synergy Supreme+ 99 bought with PCGB WEX card for discount. I'm hoping this is the best you can get. When I can't use the WEX card I use Shell.

Here's a link to a Porsche Club America video on bore scoring in M96/M97 engines. Around the 3m.30s mark they start talking about fuel. The takeaway is that scientific studies showed there is a difference in premium fuels and premium top-tier fuels in America. My take is: use the best you can get in the UK.

US fuel is a different animal to ours.

Also, be carful with Esso super, the south east, east anglia and the south of England get a 99 ron fuel with around 2% Ethanol, the rest of the UK get a fuel with 5% ethanol.

Shell tends to have less than 2% ethanol over the whole of the UK and Tesco tends to be the same.

Shell does have a slightly better additive package* that can keep injectors cleaner longer compared with Momentum 99, but round here it is £1.35 for Momentum and £1.74 for V Power.
A bottle of Wynns injector cleaner at £7.99 work really well.

Momentum plus bottle of Wynns is £85 Vs V Power at £100.

Probably use 1/2 a bottle of Wynns too.

The other thing is how often the 99 stuff is replaced at Tesco for £1.35 vs Shell at £1.74.

I know the girl at my local Shell they don't sell much of it.

*When I say additive package, watch the videos when they test to see what is in each fuel, there is extra chemicals that do break down carbon deposits, whether you think that matters or not, or there is even enough with the percentages used, is up to you.
The one issue we can suffer from with these cars though is if an injector start to get a bit clogged it no longer atomises the fuel and it can then wash down the cylinder wall. Really not good.

Slayer · 17 May 2025

Agree the price difference is about 35-40p per litre. When you have Shell and Momentum close by , why pay more for Shell?

sleevie · 17 May 2025

gizlaroc said:
US fuel is a different animal to ours.

Also, be carful with Esso super, the south east, east anglia and the south of England get a 99 ron fuel with around 2% Ethanol, the rest of the UK get a fuel with 5% ethanol.

Shell tends to have less than 2% ethanol over the whole of the UK and Tesco tends to be the same.

Shell does have a slightly better additive package* that can keep injectors cleaner longer compared with Momentum 99, but round here it is £1.35 for Momentum and £1.74 for V Power.
A bottle of Wynns injector cleaner at £7.99 work really well.

Momentum plus bottle of Wynns is £85 Vs V Power at £100.

Probably use 1/2 a bottle of Wynns too.

The other thing is how often the 99 stuff is replaced at Tesco for £1.35 vs Shell at £1.74.

I know the girl at my local Shell they don't sell much of it.

*When I say additive package, watch the videos when they test to see what is in each fuel, there is extra chemicals that do break down carbon deposits, whether you think that matters or not, or there is even enough with the percentages used, is up to you.
The one issue we can suffer from with these cars though is if an injector start to get a bit clogged it no longer atomises the fuel and it can then wash down the cylinder wall. Really not good.

Yes, great info. A lot of differences in the states. I've just found out about how they handle warranty claims and it's a lot different to Europe - but that's another thread.

I knew Esso had stopped supplying the zero ethanol fuel but didn't know about the regional variation that exists now. My regular fuel stops are in Derbyshire/Cheshire so it'll be 5% ethanol; that's not ideal.

I'm in two minds about Momentum. On the one hand I used it in the hi-compression motorbike I had until recently, without issue, so I'd expect similar good performance in the 911 - but I was only using 15L per fill, so not a big sample size. I was filling up at Tesco Whaley Bridge, interested in others experience with their fuel. On the other hand my thinking was that the 99 tanks for the pumps would be filled more frequently at the Esso/Shell garage than the supermarket. But the observations from your girl at Shell cast doubt on this.
Interestingly, I filled the wife's Nissan with E10 at Tesco, Ryde, IoW today. I would have used Momentum but big sign at entry "Momentum not Available" and Momentum pumps locked. Not an issue for the Nissan. The wife normally uses the green pump from the closest garage to where she is when she decides to fill up. I just give it a dose of 99 from time to time to help clean things out and get the ethanol level down.

The Wynn's Injector cleaner is a good idea. The PCA video also recommends injector cleaner, at a frequency as low as only once a year for low milage Porsches. I've never used it but I think I'll get a bottle to have on hand.

My last Porsche fill-up was at Shell, Chelford. Close to Alderley Edge where the Supercars roam so I'm hoping the 99 tanks get good usage and the fuel is not too old. Based on this post I won't be rushing to fill up at Esso and hopefully get some feedback on Momentum from Whaley Bridge.

sleevie · 17 May 2025

Apologies for the long winded reply but one other thing to add. I got my used oil analysis back this week. See post on Millers UOA - add yours.

The good news is I got zero fuel dilution and low deposits. So the Esso/Shell fuel is working well in that respect. Soot and ash levels low, keeping injectors clean, getting good spray atomisation.

gizlaroc · 18 May 2025

That Tesco at Whaley Bridge was really busy when I filled up there a few weeks back, mind you, it snowed so maybe everyone was panic filling?

We were over in Hayfield.

My Shell is in Waitrose, so 99% of the cars going in are Range Rover diesels or Nissan Micras.

I would happily use Esso, Tesco or Shell, but originally the Esso 99 had less than 1% ethanol, that changed to around 2% and then it was found out that is only certain parts of the country.
Also, it got to the point where Shell was only 5p more, so used that.

But I go past the Tesco and so fill up with that or Shell now. But would happily use any of those three.

nick38 · 18 May 2025

Can one of you guys explain what difference the ethanol % makes please?

sleevie · 18 May 2025

I'm a bit old fashioned so bare this in mind and it skews my preferences. For modern high-performance sports cars E5 is generally safe and acceptable, however, neat petrol (if high-octane) might yield slightly better fuel economy, throttle response, and consistency, especially if the engine is tuned for it.

Ethanol attracts and absorbs water from the atmosphere. This can lead to: corrosion in fuel systems. Fuel separation (phase separation) in long-term storage.
Reduced shelf life — a concern for cars not driven regularly (e.g., collector cars).

Less Predictability for Tuning. Ethanol blends can vary slightly in composition depending on the supplier and conditions. This can complicate precise engine tuning for peak performance in high-strung engines.

Like I mentioned previously, I've no issue with my wife refuelling her Nissan with E10 but given the choice I wouldn't put an ethanol blend in my Porsche.