Jon just done a quick check on Scoobypedia and if you have a new age car you'll have to reset it through the diag port next time you get it serviced etc.

If you have a classic it is as described earlier (the connectors you need to short are illustrated at reference). Not sure which one you've got

I'm actually a bit surprised that some Coop owners still dont know the benefits from using the higher ron fuels. The very same question has been on the go for years & on most car forums,[ well at a guess]

If you want to run cool, you need heavy heavy fuel!