Its size is small at less than 50 centimetres in length and 65 in height. The component layout has been designed to ensure it takes up the smallest possible space. Yet it guarantees the same advantages as bigger engines because it has not been reduced but miniaturised.

The power unit has thus been built to ensure the greatest rationalism, efficiency and reliability and is the smallest Common Rail four-cylinder diesel on the market. The only power unit that can pack no fewer than six normal-sized components into a cylinder with a diameter of less than 70 mm. In other words, four valves, an injector and a glow plug. The engine also adds another record to this major feat of miniaturisation: it is the most powerful. Despite a truly miniscule cylinder capacity of 1248 cc, the pocket Multijet comes out on top when compared with all the small diesels with fixed geometry turbines currently present on the market. Even the most vaunted. Suffice it to say that it offers the best specific performance of any diesel engine with 800 to 1500 cc of cylinder capacity. Power output of 41 kW/l and torque of 116 Nm/l.

This compact, technologically sophisticated engine also offers outstanding efficiency and is practically guaranteed for life. The 1.3 16v Multijet is designed to last for 250,000 km instead of the usual 150,000. During this long lifetime, it does not require any maintenance to mechanical parts (even the normally essential fan belt change at 80,000 km is not required). The oil change intervals have also been increased from 20 to 30,000 km. The oil is naturally low viscosity (i.e. designed for fuel economy) and environmentally friendly.

The 1.3 Multijet 16v is environmentally friendly because it already meets Euro 4 emission limits not due to come into force until 2006. It is also one of the very few cars in the world that has been able to achieve this result without the need for a sophisticated exhaust post-treatment device such as a particulate trap. All in all, an intrinsically clean car: the particulate emission level (responsible for dust and fine dust) - for example - is even lower than that established by the forthcoming Euro 4 standard.

Fiat have recently upgraded the tiny engine, introducing a 75bhp version of the 1.3-litre Multijet at the Frankfurt IAA in September, while the 'family' capability has also been enhanced by the arrival of a 90bhp version that makes use of a compact, variable nozzle, turbocharger.