Supermarket petrol

[Pine]

I am one of those who normally prefers to steer clear of supermarket petrol in favour of branded petrol. In this area that’s a choice of Esso or Texaco.  However recently when the low fuel warning light came on the first place I passed was Tesco so I stopped and filled up with 35 litres of Tesco 95 RON unleaded.
Well, I almost hate to admit it but the car is running beautifully. Tickover seems smoother than normal and it is nice to drive. I have only done 100 miles since filling up so it is too early to make a judgement but the mpg may have improved.
Has anyone else noticed a difference between different brands of petrol and which do you prefer?

[Geoffers]

Hmmmmm! I've recently changed to branded (BP etc) only and find that I get 5-10% more mpg!

[guest221]

I've not noticed any difference with the Jazz using either supermarket or branded (or 95 vs 97 super either) but both the Mondeo TDCi and CR-V diesel ran better on BP Ultimate, at least once into at least the second tankfull. My theory is that diesels are more sensitive to varying fuel quality as (I'm told) the fuel acts as a lubricate.

[JazzyB]

I got a 5p off coupon from tesco today but the price has gone up nearly daily so any saving is wiped out!!

[nowster]

Supermarket fuels from Tescos and Sainsburys seem to be OK. I've had less success with those from Asda and Morrisons. When available (and roughly the same price as the supermarkets) I'll preferably fill up with a branded fuel (eg. Shell).

Forecourts with high turnover may not allow their tanks to settle for enough time after being refilled by tanker. This could cause the fuel to be damp or dirty. That said, the raw fuel used in all petrol stations (both supermarket and branded) comes from the same refineries. The only difference is the big bottle of additives that the tanker driver adds to the mix when picking up his load.

[guest671]

I prefer to avoid Tesco petrol because I am sure I get less mpg and the engine does not run so well. I generally only use it when I get a 5p off coupon! I find the best petrol is BP.

[guest869]

I seem to remember reading about  a test where the Tesco super uleded came out the best compared to other super unleaded fuels.

Here it is http://www.pistonheads.com/GASSING/topic.asp?h=0&t=569947&nmt=Tesco%20Super%20Unleaded

Interesting reading

[nowster]

I'm not sure whether a 1.34L engine would benefit from a high octane fuel, or whether the engine management unit of the Jazz would take advantage of it.

I've used Shell VPower without noticing much difference. I did fill with Asda standard unleaded once, and noticed that I was stalling the engine occasionally for a few days afterwards.

[culzean]

The 'old' 1.4 Jazz engine ( the 2002 to 2008 DSi) has a 10.8:1 compression ratio, this is very high for a petrol engine and it needs the twin spark plugs per cylinder to control the 'pinking' (pre-detonation of fuel).  The DSi engine does benefit from 'super' fuel whether it is 'V' Power or Ultimate (both 97RON), I know mine runs smoother with more mpg. The DSi engine will burn 95RON but from my experience it likes 97 better.
My wife used to fill up her jazz with supermarket fuel and it always felt sluggish compared with mine, but a few tanks of the good stuff sorted it out, now she doesn't use 'junk fuel' in her Jazz any more.

As a bonus, the additives in the better fuels help to keep the engine and fuel system cleaner as well.

[Bob3356]

Tesco fuel...... some of you people seem to have short memories.

[guest598]

At the moment i am using Shell which is the same price as sainsbury's i think i am getting better performance.thats in a 1400 ex vtec.

[guest684]

I have certainly found Sainsbury's 95 fuel causing my engine to run smoother with a sound more akin to a healthy 'plastic-clockwork-diesel'.

But I have certainly noticed a small but noticeable performance gain (ie. lack of flatness in the acceleration curve) with BP/Shell 98.

As for mpg, I do find Sainsbury's 95 to be best with gentle driving!!

[guest593]

I used to use Asda or Tesco for my fuel but read somewhere, may have been on here, that there is a noticeable difference in mileage and engine running when using petrol from branded forecourts so I did my own experiment.
I found that my engine did indeed run better and I did get more MPG with branded fuels. I have also noticed my Jazz seems to like Shell petrol the best.
I carried out my experiment after doing a long journey which, I'm convinced, cleaned out all the crap engine.