For diesel, 2014 wasn't the best of years. This fuel has had a bull run since the late 1990s, when the first generation of direct-injection turbocharged engines began appearing. 

I have fond memories of spending the 1998 Christmas holidays in a 150bhp Mk4 Volkswagen Golf TDI. On Boxing Day that year, I drove from Hertfordshire to Norfolk in convoy with a first-generation Audi S4 Avant. On the slingshot roundabouts of the A11, the mighty turbocharged petrol Audi had some trouble keeping up with the exit speed of the diminutive Golf.

This VW seemed to be the future: light on its feet, well packaged and with the kind of mid-range acceleration that left most regular ‘performance’ cars struggling. Indeed, such was the Golf’s mountainous torque curve that it was not beyond losing traction in third gear.