alistairolsen

That sounds like diesel bug, which is an algae like organism, its horrific on boats where consumption is low and tanks are warm

Farmer Giles

I've done a similar experiment with tesco v's BP running the car on each fuel for one month under similar driving conditions, school run, shopping, occasional M'way outing.

Car is a 2010 Kia Ceed 1.6 CRDi.

Whilst I didn't notice any difference in performance or how the car would drive, start etc. the BP fuel consistantly returned a 10% increase in fuel economy over the Tesco fuel.

average for each tank :

Tesco : 40mpg
BP : 44mpg

2p

4parajon

I do 30-40,000 miles a year in my Merc & use whatever is the cheapest diesel fuel, which is generally Asda & I've never had a problem using any supermarket fuels. We also use the same in the works renaulty traffic van & again, never had any issues.

Glenn_

iTrader: (1)

Ive never been bothered about mpg. You need fuel for your car so just put the fooker in.

gcfcos

Lol I had thought the same. Never worked out mpg just miles per £20 lol

massivewangers

iTrader: (1)

I do 5-600 miles a week and I tend to avoid supermarket fuel, as don't get the mileage out of it when compared to the Shell places I normally use.

A friend had a company car, used to do over 1k a week and he said it made a difference. He used to be told to use an Esso station local to his office as it was always cheap, but he said the MPG the car returned was noticeably lower than when he used other places.

If you do 100 miles a week then you probably won't notice, but if you do a lot, it makes a difference in my experience.

4parajon

As I said I do a similar mileage so will have to try a tank of both Asda's & a main brand to see if it's true.

It's Czech Mate

Its not just (even?) the mpg.....its all the additives that protect/lubricate/de-coke etc....its hard to tell if you constantly switch from one to the other, or have the odd tank of branded......i'd bet a large amount of money that if you ran two identical cars from brand new to 100k miles, one on optimax and one on asda fuel exclusively then there would be a significant difference in wear, performance/economy and parts replaced

3i Jim

I bet the one with asda fuel will wank out the injectors first.

nevsrevs

bio bug is bad news, the fuel is hygroscopic, attracting water, this then becomes a breeding ground for the bug. that then creates sludge. I have a big problem at the moment on all my big oil boilers running on bio, the char vaule of the fuel is terrible. got the fuel analysed and it contains traces of paint stripper, brake fluid, meth spirit, and other nasty shit. basically its 70% kerosene added with what ever other shit there can get there hands on, then palm it off as bio.

mjonathan24

iTrader: (1)

I think it totally depends on the car, I had a Clio 182 a few years back and I used to run it on momentum 99, it started to have a few problems starting, switched to Sainsbury's 97 and it ran fine. Then had a megane 230f1 which loved momentum 99, so does the saph, but my zetec mk2 fiesta prefers Sainsbury's 97.

Bailes1992

I do anywhere from 300 to 1200miles a week so MPG is important to me as my travelling expenses rarely cover my actual travelling costs.
Using Supermarket diesel I struggle to get 50mpg. BP or Shell will return me 60-65mpg on a run and BP Ultimate or Shell V-Power consistently return me over 70mpg.

There must be something different between the fuels.
I tried Texaco Supreme once. Made the car very smooth and very quiet but MPG was very poor.

4parajon

I know this seems awhile ago now, but I thought it was worth putting up my results based over a few weeks for everyone to see.
Car is a 64plate new model Merc C Class AMG Line 220 diesel Estate.

19/02/15 - 62.11litres of Asda regular diesel, completed 650miles avg 47.8mpg, fuel cost £1.12p/l total of £70.00

24/02/15 - 62.46litres of Shell regular diesel, completed 616miles avg 45.5mpg, fuel cost £1.169p/l total of £73.02

7/03/15 - 62.3litres of BP Techron Supreme diesel, completed 658miles avg 48.7mpg, fuel cost £1.239p/l total of £77.18.

Not a scientific test by any means, but it does show there all fairly consistent mpg and IMO it's not worth shelling out the extra money for the alledged better fuel. I also could'nt tell the difference in how the car drove with the different fuels added.

It's Czech Mate

Absolutely

The reason I wont use supermarket fuel isnt anything to do with the mpg....its the long term health of the car as the cheaper fuels lack the protective additives.

If its a company car then game on