What Car? True MPG was launched in April, to help car buyers find out what fuel economy they can really expect from their new car.
There's never been a greater demand to discover which cars have the best mpg, and What Car? True MPG uses state-of-the-art testing equipment, on real roads, to give you a realistic figure.
Wherever possible, we test every car we drive in the UK. Since we launched True MPG, we've added a huge number of cars to our database, ranging from cheap city cars such as the Fiat Panda to luxury saloons such as the Porsche Panamera. If the model you're looking for wasn't listed last time you looked, it's well worth revisiting True MPG now.
Recently added is the Toyota Prius+. Despite being larger than the Prius it's based on, the Prius+ MPV performed better in our True MPG tests, returning an average 54.6mpg. That's down on the 68.9mpg official figure, but better than the Prius's 52.2mpg.
Toyota Prius+ averaged 54.6mpg in our True MPG tests; better than standard Prius
The Toyota GT86 is another recent addition. Unusually, our average True MPG figure was an exact match for the official figure, at 36.2mpg.
One of the trends in our results is that cars with large petrol engines tend to get close to official mpg figures. The Jaguar XK8 5.0 V8 Convertible, for example, has a True MPG average of 24.9mpg, compared with an official average of 25.2mpg. The V6-powered Lexus GS250 achieved 30.9mpg in our tests, just 0.8mpg shy of its official figure.
Diesel-powered SUVs have performed strongly, too. The Mercedes ML250 Bluetec averaged 37.5mpg, which isn't too far off the 44.8mpg official figure, while the Volvo XC60 D3 AWD averaged 43.6mpg in our True MPG tests, just 6.0mpg down on the 49.6mpg official figure. Importantly for many buyers, it averaged 42.9mpg in urban conditions.
Diesel-powered SUVs such as the Mercedes-Benz ML250 Bluetec have performed well in True MPG tests
BMW's Efficient Dynamics technology is designed to reduce fuel consumption and has helped to deliver reasonable real-world figures in our tests.
The most efficient version of the BMW 3 Series is the 320d Efficient Dynamics, which has changes over the standard 320d that boost its official average from 61.4mpg to 68.9mpg. In our True MPG tests, however, the Efficient Dynamics model didn't have such a large advantage - it averaged 56.0mpg, a 1.2mpg improvement over the standard 320d.
BMW 320d averaged 54.8mpg; the Efficient Dynamics model gave a 1.2mpg improvement
If any car ought to deliver good mpg, it should be a diesel-engined city car such as the Fiat Panda 1.3 Multijet. Sure enough, it's one of only two cars so far to crack the 60mpg barrier, with a True MPG average of 61.0mpg.
That's almost a match for the best-performing car yet - the Kia Rio 1.1 CRDi Ecodynamics 5dr, which averaged 70.6mpg.
Visit the True MPG website and you can find the True MPG figure for your car, tailored to how and where it'll be driven. There's also a guide to how the tests are conducted, and advice on how to save fuel.
Our reviews are based on hard data and thorough testing in the real world.
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