Audi A5 Coupe TDI – along with the rest of the A5 range, all Audi A4s and Q5s – will now be fitted with misfuelling filler neck: so you can’t put petrol in your diesel car

Business Car Manager: Editor’s Blog

I COULD have done with this when I had my Audi A4: a fuel filler neck that prevents you from misfuelling. As it was, my wife Alison kindly filled the car for me the day before I was due to go to a meeting and inadvertently poured petrol into the diesel tank.

It’s easily done. Some 150,000 drivers do it every year. The AA even has specialist units that attend to members that have misfuelled.

Yet car makers such as Ford have been providing the technology for years on their cars