Poor MPG with Tesco fuel

Captain_Proton

I own a 1997 Fiesta which I normally fill with unleaded petrol at the local ASDA or Sainsburys stations. I always keep a log of my mileage when re-fuelling and how much I put in to fill the tank to capacity. This means I can use the figures to calculate how many miles per gallon the car is achieving - figures are typically 40mpg for local runs only, and 45mpg for long distance main road and motorway runs.

However, recently I filled the tank from almost empty with unleaded at a Tesco station, and since re-filling again I have calculated that my fuel economy using the Tesco fuel was only 35mpg (and this included a couple of long motorway trips).

Nothing else could have affected the fuel economy - I always keep my car in good condition, keep tyres at correct pressure etc, and the weather during the period of using Tesco fuel was not abnormal. My driving style also remained the same. Since re-filling with fuel from ASDA, the fuel economy has returned to normal levels. The only other time I have experienced 35mpg with my car was during the snow in December, when driving conditions were poor along with the low temperatures.

A friend of mine says he has experienced similar poor mpg with his diesel car, along with poor performance caused by Tesco diesel, and has since stopped using Tesco fuel.

I'm just interested in whether anyone else has experienced this problem too, and what the possible explanation could be. It seems wrong that Tesco fuel should provide less "bang for your buck" than fuel from other retailers.

System

I see that with Tesco diesel as well, but get good returns from ASDA.

Be prepared for the plethora of people trying to shoot you down for daring to say there is a difference in the fuels. It's happened before and it will happen again. There are just some people that can not accept that there are people who do not get the same results as themselves.

Jinx

Ooooh Ive just filled my car at Tesco, must keep an eye on it more closely this week to see if its less!!

worried_jim

Richard Headland, Editor, Which? Car, says:

“For many cars it’s a waste of money paying over the odds for so-called ‘super fuels’. The standard fuels we tested were all up to the job, whether from a major fuel brand or a supermarket. There’s no conclusive evidence to show that super fuels are better for your car in the long run - so in a time of high oil prices, why would you choose to pay more?”

http://www.which.co.uk/about-which/press/press-releases/product-press-releases/which-magazine/2008/09/not-so-super-fuel/

Use supermarkets. The supermarket petrol Which? tested was equivalent to Esso and Shell 95 Ron fuels in performance and economy terms.

Captain_Proton

I can see how this topic will spark debate, let's hope it's healthy! I guess it will depend on a number of factors, and possibly the fact that I am driving an older car will produce different results than more modern cars. I do know that modern petrol cars can cope with ethanol addition in petrol better than older cars - does Tesco stick more ethanol in their petrol than other retailers?

adamc260

Shell fuel is the same price as tesco fuel where I live... so I always opt for Shell

Hintza

adamc260 wrote: »

Shell fuel is the same price as tesco fuel where I live... so I always opt for Shell

Me too except it's Asda versus Shell.

System

worried_jim wrote: »

Richard Headland, Editor, Which? Car, says:

“For many cars it’s a waste of money paying over the odds for so-called ‘super fuels’.

??? Nobody mentioned superfuels. We are talking about standard fuels be they supermarket or oil company.

Captain_Proton

!!!!!! wrote: »

??? Nobody mentioned superfuels. We are talking about standard fuels be they supermarket or oil company.

In my case it's more Tesco rather than supermarkets in general. For convenience I usually fill up at ASDA and Sainsburys, and haven't seen any significant difference MPG wise between them and the likes of Shell, Esso and BP. However, Tesco petrol seems to cause a significant drop in MPG for my Fiesta (5 mpg less means that it is doing 50 miles less to the tank).

Hammyman

Any MPG difference is usually in peoples heads.

Captain_Proton

Most people don't keep a fuel log but I have always done so, it's a meticulous habit passed to me from my father! From time to time I plug all the figures in a spreadsheet so I can keep an eye on the MPG - good for fault finding. The MPG with Tesco fuel certainly stands out, I thought there may have been a problem with the car at first but everything checks out fine, and the MPG has returned to normal since going back to ASDA petrol. Certainly my 1.25 litre Fiesta shouldn't be drinking fuel like a 1.8 Mondeo, but it does with Tesco petrol!