this is the thing though i dont put my foot on the gas , the induction kit is not evan 2 months old i checked it yesterday and it is still as clean as when it came in the box,if i put magnecor leads on it when it goes in for a service will they take them off and change them

Ultimate is suited more to a turbo engine anyway.

A focus ST will adapt to Super because there is a map built into the PCM for super.
As soon as the car senses that you've put super in it will switch to the different map.
The Fiesta ST can't and just runs rich (which has got to bugger the cat up eventually???)

People really are wasting their money on Super Unleadeds as the Engine ECU ignores it.
The car is only mapped for BP 95RON Unleaded. Some 95RONs are as good as BP (Shell) and some are worse (Tesco)

so have i been harming my ST then ,

Not so much harming it just wasting your money.

Once you go back to 95RON you'll notice the difference

well thanks for all your help and saving my money means i can do more to the ST than put v power in. will let you know if anything changes

cheers howick17

I heard somewhere (maybe on here) that the high octane stuff shouldn't be used on the Fiesta. I know a lot of people that do use it and have no complaints but i run mine on 95 and it's runs sweet. No supermarket fuel though, just shell and BP.

I noticed a considerable difference in my fuel consumption when i took off my induction kit.

oops it took me so long to type that (was making a cuppa tea) that you already had the conversation lol

thanks everyone , well i will start using normal shell petrol just put 35 quid of Vpower in yesterday lol. Will let everybody know how i get on

thanks again Howick17