BMW 320D EfficientDynamics beats Fiat 500 Twin Air in fuel economy

Coincidentally, at the beginning of this year, both my wife and I started to drive new cars.

We selected new cars based on fuel efficiency, a "green car" with  Energy Label A. Ania was “sold” when she saw the Fiat 500 Cabriolet. I was long awaiting  the BMW 320D EfficientDynamics February introduction.

This car  with an eight-speed automatic transmission has an amazingly efficient engine. My average fuel consumption over the last 46000 km, indicated by the board computer , is 4.6l /100km.  No wonder that it got a 10/10 Green-Car-Guide rating!

Unfortunately, while my wife was enjoying the Fiat 500 driving and its beauty, its fuel consumption was very disappointing. Average fuel consumption reported by the board computer over the last 2500km is 7,2l /100km !

I decided to test both cars myself on the motorway between Best and Amsterdam (111km in total) during a very relaxed traffic conditions ensuring no traffic jams and allowing constant speed between 90 and 110km/h.

The BMW fuel consumption was amazingly low. Far below the technical specification !

The board computer indicated 3.2l /100km but based on the fuel refilling the calculated fuel consumption was 3.93l/100 (average speed 98,2km/h)

The Fiat 500 lost the competition . Indicated , by the board computer fuel consumption was 4.2l, based on refilling data 4.6l despite lower speed adjusted to minimize constant fuel consumption (average speed 86km/h )

BMW fuel costs (6,77 Euro) were 32% less than the cost of the benzine consumed by Fiat 500 (9,96 Euro) !

As I can recommend BMW 320D EfficientDynamics as the best green car in this category I definitely discourage everyone, expecting low fuel consumption, from buying Fiat 500 Twin Air. 

It looks like I am not the only one experiencing very high fuel consumption by the Fiat 500 Twin Air. If you Google for “Fiat 500 Twin Air High Fuel Consumption” you will find hundreds complains. 

In “Eco warrior: Fiat 500 Twinair” you can read “

“But if the drive had been fun and a convincing demonstration of the 500′s ability to be genuine allrounder, it did expose one of the 500 TwinAir’s major weaknesses – fuel economy” 

Real World Car Fuel Consumption v Official Figures describes a case of a Fiat 500 Twin Air driver complaining to BBC about high fuel consumption “he was regularly getting 35mpg and couldn’t understand why when Fiat claim that the 500 will return 68.9mpg as a ‘combined’ figure with up to 76.3mpg on the ‘extra-urban’ cycle.”

My wife complained about the high fuel usage to the Fiat dealer in Eindhoven but she was informed that if this problem is known already on the Internet they can’t do much about it

The only way to put pressure on car manufactures is to start collecting real fuel usage from consumers themselves and publish fuel usage statistics. Smartphone apps open this opportunity and I expect that consumers, very soon,  will be able to confront car manufactures with real numbers, not as individuals, but as driver communities car manufactures won’t be able to ignore anymore.

In the meantime I hope Fiat will provide my wife with advise how to drive Fiat 500 Twin Air economically.

Yesterday (17-11-2012) we agreed with the Fiat dealer at Pietersbergweg in Eindhoven a one week fuel consumption test starting 27-11. However I do not expect much from this, as the dealer confirmed that the fuel usage stated in technical specifications are based on the labs tests and the real-world fuel consumption figures are much higher. The dealer referred to much higher fuel usage by their Fiat 500 Twin Air show model making only 12km on one litre (8,3l per 100km !) .
I agree that the real-world fuel usage can be higher than measured during labs tests. But 80-100% higher usage is misleading consumers and if this is the case Fiat 500 Twin Air should never get a Green label and Dutch tax benefits.