Alfa Romeo 159

A Short History of Alfa Diesel Engines, part one. Back in 1997, the Alfa 156 1.9 JTDM became the first passenger car in the world to use common-rail tech - a high-pressure fuel injection system that replaced boggo low-pressure pumps. Most diesels use it now, and other car firms have developed spanglier versions.

Twelve years on, Alfa has decided it's time for its own update. Enter the new 2.0-litre JTDM - seen here in the 159. It's a modified version of the outgoing engine but this time it meets EU5 regs while producing 20bhp and 30lb ft more than before.

It's strong and quick and typically turbodiesely, but lacks the last notch of finesse you find in cars like the 3-Series, C-Class, A4 and even the Insignia. It's hardly loud but isn't as hushed as it should be - you're always aware it's there - and there's an oddly distant whine coming from the engine, like some sort of high-pitched alien frequency. The gearchange feels a bit knobbly too; the lever never seems to slot crisply into place.

This might sound a bit harsh - neither flaw is a huge problem - but for £23,850 you can reasonably expect something much closer to perfection. The competition can manage it, after all.

Of course, those gorgeous curves still make this a wonderful-looking car but, as Alfa Romeo knows better than most, beauty is only skin deep.

Dan Read