04 June, 2012
Diesel engines used to be noisy, smelly and somewhat agricultural. Then car makers wised up, made the engines cleaner, more powerful and refined, and with diesel cheaper than petrol at the pumps, the fuel suddenly became more viable. Not for long. With the Chancellor making diesel pricier than petrol, choosing between the two fuel forms is now no longer as clear cut.
If it was purely down to miles per gallon, diesel would win. Easily. A Ford Fiesta 1.4 TDCi returns a quoted Combined consumption of 69mpg. The petrol equivalent of the same capacity does 49mpg.
But petrol hits back with the model’s purchase-price advantage. The petrol Fiesta in three-door Edge trim would set you back £12,195. The diesel version costs £12,995. And the difference isn’t going to get smaller. Ford Powertrain’s director Andrew Fraser explains: “Diesel engines are getting more expensive to build due to increased legislation. Last year a diesel particulate filter (DPF) had to be fitted, which required an injection upgrade. In 2015, they’ll have to abide by Euro VI emissions standards, so most diesel engines will need a Nitrogen Oxide trap. It’ll all add up to making the payback period for diesel longer.”
The addition of DPFs in particular has been contentious. Vanessa Guyll from the AA’s technical services says: “The DPF and exhaust gas recirculation mean diesels really aren’t viable for short journeys and town work. The DPF doesn’t get hot enough to clear itself out. We get called to about 700 breakdowns a month for blocked DPFs.
“For anyone who potters around town and doesn’t do journeys that are a minimum of 10 miles we wouldn’t advise a diesel. Any savings owners might make on road tax would be quickly wiped out by fixing problems with the emissions equipment if usage isn’t suitable.”