supermarket petrol

There may be minimal differances but nothing to be concerned about. I've been using Sainsburys ordinary unleaded in my V6 sports car for over a year now and I get better mpg out it than using Shell Optimax or BP Ultimate.

It's not just supermarket ones, nor is it only performance vehicles.

My humble 1.3 Hyundai Accent is distinctly displeased with Esso or Tesco fuel. It runs a lot smoother with virtually anything else, but it hates these two. There's no loss of economy that I can discern, but the engine is noticably noisier and rougher, and it can't be doing it much good.

I used Tesco and Asda deisel from new for 6 months. Then after reading a thread on here, ran the tank low and filled up with shell. After the second filling with Shell my mpg increased by 4 to 45.5mpg. The Shell deisel was 3p/litre cheaper too.
Also experienced some stalling but not since using Shell.

until recently i wouldnt have beleived this sort of thing,
but whilst on holiday (last week), my vauxhall zafira 'engine management system' console light came on and stayed on, after taking it to a local garage in wadebridge, cornwall.
the fault was identified and cleaned (saving £100 for new part), when i talked to the mechanic, he asked about fuel, I always use asda, filled up before travelling to cornwall, then filled up with esso, 3 days later light came.
after garage had solved problem, drove away and later on put more petrol in from esso, within miles the light had come back on, this continued until I got home on saturday, went to asda sunday, filled up, light went off, came back on, it has now gone back off...

the mechanic had said, that supermarkets fuel doesnt have the same additives as esso/shell/bp etc........ which sounded feasible, but i remember this discussion before and the argument about whether a fuel lorry will visit different petrol stations during the the same load.......

makes you wonder though.

anyway I think my Zafira doesnt like esso .... and as asda is well cheaper, will stick to that, unless some can prove there is a difference

balsingh wrote:

If you look back to the 80s, there used to be 3 grades of fuel, 2*, 3* and 4*. Most cars woudl happily run on 2*, but 3* and 4* had additives to make the car run better (but it cost more). In essence, the same difference between the supermarket and Esso/Shell fuels now.

Petrol used to be sold in 2*, 3*, 4* and 5* ratings. However, this had nothing to do with what, if any, additives were included in its composition. The stars denoted the octane rating of the petrol The higher the star rating the higher the octane rating. High performance cars usually had a higher compression ratio and therefore required a higher octane rating. This could be altered by retarding the timing, but then they did not run as well. Your average family saloon would normally run on either 3* or 4*.

And, of course, the main additive in those days was lead!!