You’d be amazed how much good a couple litres of Petrol in a full tank of diesel can do. We had a work van, a older Peugeot Partner (think it was approaching 170k miles and 8 years old at the time) and I put a tenner of Petrol in it by mistake once, immediately panicked and called the boss – he sent someone down with the fuel card and we filled it to the brim with diesel. Never missed a beat and ran better than it had in years afterwards.
This is NOT a recommendation lol, do this at your own risk, and definitely not in your Motability car lol
"Man is born in freedom, but he soon becomes a slave, in cages of convention, from the cradle, to the grave."