BMW 3-Series: Final score

Diesel or petrol?

The 318d has certainly proved an economical choice, but it's proved almost impossible to achieve the 60mpg average BMW claims it can do. Despite every eco-driving trick in the book, the fact that my route to work involves tackling twisty and hilly roads means i'm always going to struggle. Of course if you spend the majority of your time on motorways thrn you're more likely to get close. 

But is the 318d the best value for money choice in the range? Given that the BMW 318i should do a claimed average of 47mpg it isn't exactly a petrol guzzler. What's more, at more than £2000 cheaper than the diesel, you have plenty of spare change to fill up at the pump.

Using our unique petrol vs diesel calculator the astonishing fact is that you'd need to cover almost 200,000 miles (if you chose a 318d over a 318i) before it started to save you money.

However, the diesel does offer quite a different driving experience relying on low down pulling power which makes for a more relaxed and, I have found, smoother drive. Of course, whether that is worth the hefty premium is down to personal choice.

Current mileage: 8779

Average mpg: 52.8