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A diesel Porsche? So that'll be its most efficient car then?
Actually, no. Amazingly, the new Cayenne diesel is only Porsche's second most efficient car with a fuel figure of 30.4mpg.
The most efficient Porsche is currently the two-seat petrol Cayman with semi-auto, double clutch gearbox. It returns 31.0mpg, but the diesel is far more business-relevant - as much as any £40k large 4x4 can be.
Essentially the Cayenne's diesel is the same found in the Audi Q7 or VW Touareg. However, Porsche's engineers have made their car feel more sprightly, with better response from the gearbox and accelerator.
Porsche has also worked hard, and successfully, on suppressing diesel clatter by including a specially insulated windscreen and fitting more insulation to stop noise transferring from the engine bay to the cabin.
While we don't yet have full cost per mile figures, fuel consumption is broadly in line with equivalent rivals such as the Range Rover Sport, BMW X5 and the aforementioned Audi Q7.
The Cayenne combines ride comfort with a sporty drive better than these rivals, while Porsche also claims that residual values on the Cayenne are class leading.
What lets the car down, however, is that the interior isn't at all exceptional. Maybe this is something the next generation Cayenne, due in a little over a year's time, will address.
Porsche is to be commended for doing a diesel, but while the Cayenne is a good car, it doesn't feel that special.