Volkswagen’s Polo BlueMotion is a bit of an odd fish: a current generation VW Polo has been kitted out with various bits and pieces to improve its fuel economy. The result is about 15 percent more miserly than equivalent 1.4TDI models, with the base-model BlueMotion 1 even achieving a Prius-trumping official CO2 emissions score of 99g/km.

Unfortunately the gains don’t come without pain. The aerodynamic add-ons front and rear are nice enough, but the gearbox has been fitted out with longer ratios in third, fourth and fifth and we have to say that, as a result, it’s not a pleasant thing to drive.

Changing up from second to third feels like half the engine must have fallen out and is bouncing down the road behind you. Third comes as a surprise because in the first two gears the three-cylinder turbo diesel feels eager in the extreme – positively rapid, with the usual ample torque of a compression-ignition engine providing plenty of urge to get you going. But as you get to third, you’d be forgiven for thinking you’d found fifth instead. Actually, slot from second to fifth by mistake and the engine will splutter so hard it might have choked on a breeze block.

The best way to get up to normal road speed is to hang on to second until you hit the (rather low 4,500rpm) red line. And then do the same with third and fourth. Don’t even think about fifth until you hit 60mph or a downhill stretch with the wind behind you.

Driven this way the Polo will at least escape the feeling that it’s about to start kangarooing in protest with every upshift. But of course this is not the way to get the car’s claimed 70mpg+ fuel economy.

In summary, it really shows that this is an existing car modified to be miserly, not one for which such extremes of economy come naturally. The Polo BlueMotion is crying out for a properly spaced 6-speed gearbox and until it gets one – most likely with the next model Polo – we’d advise opting for one of the conventional Polo 1.4 TDI variants. They’ll feel nicer to drive, will be very nearly as frugal, and will cost less to boot.