Each is powered by a version of BMW's versatile 2.0 litre turbodiesel inline four, with varying turbocharger trims and engine tunes allowing a wide spread of fuel economy ratings and power outputs.
With a fuel consumption of just 4.5 l/100km, the 118d is also the most efficient BMW on sale in Australia.
Voted the 2008 World Green Car of the Year, the 118d emits only 119 grams of carbon dioxide per kilometre.
The 2.0 litre turbodiesel produces 105kW and 300Nm of torque, enabling the 118d to run to 100km/h in 9.5 seconds.
Available in hatch, coupe or convertible body styles, the 118d is one of the most fuel-efficient convertibles on the market today, consuming 4.9 l/100km in convertible form.
Available with a six-speed manual transmission or a six-speed auto, the 118d features brake energy regeneration and electric power steering, with manual-equipped models also scoring an auto start/stop function and an efficiency-promoting optimum shift indicator.
Aerodynamic panels and on-demand ancillaries such as the air-conditioning compressor and alternator are standard features, working to reduce engine load and aerodynamic drag.
Like the 118d, the 123d is available in hatch, coupe and convertible form. However, with significantly more power and torque coming from its twin-turbocharged TwinPower 2.0 litre diesel engine, the 123d is undoubtedly the performance model of the 1 Series diesel range.
The 123d develops 150kW and 400Nm of torque, the latter of which is available from a low 2000rpm. That endows the 123d coupe and hatch with a 0-100km/h sprint time of just 7.0 seconds when fitted with the six-speed manual transmission.
The 123d lists a fuel consumption figure of 5.2 l/100km, and features auto start/stop and an optimum shift indicator.
Both auto and manual-equipped models get the drag-reducing aerodynamic panels, as well as brake energy regeneration and on-demand alternators and air conditioning compressors.
|118d Sports Hatch 6-speed manual||$42,170*|
|118d Sports Hatch 6-speed steptronic||$44,370*|
|123d Sports Hatch 6-speed manual||$50,790*|
|123d Sports Hatch 6-speed steptronic||$53,590*|
|123d Coupe 6-speed manual||$57,900*|
|123d Coupe 6-speed steptronic||$60,864*|
|118d Convertible 6-speed manual||$52,900*|
|118d Convertible 6-speed steptronic||$55,655*|
|123d Convertible 6-speed manual||$67,200*|
|123d Convertible 6-speed steptronic||$70,164*|
* Manufacturer List Price is shown and excludes dealer charges, stamp duty, statutory charges and on-road charges which are additional and vary between dealers and States/Territories. Customers are advised to contact their nearest BMW dealer for all pricing inquiries.