A new version of ZF's eight-speed automatic transmission will be offered across the range, and its revised hardware and software helps to improve efficiency further; the 116d auto emits 96g/km of CO2. There will also be a manual gearbox-only 116d Efficient Dynamics, which uses a switchable coolant pump and combustion chamber pressure control to lower its CO2 emissions to as little as 89g/km.
There are also three 2.0-litre diesels, badged 118d (148bhp and 104g/km to 99g/km), 120d (188bhp and 114g/km to 109g/km) and 125d (221bhp and 121g/km). The first two of this trio will be offered with xDrive four-wheel drive, too, although the 118d xDrive will be restricted to a manual gearbox and the 120d xDrive is available only with the eight-speed auto.
As with the diesels, the UK won't be getting the most basic petrol engine, badged 116i; it's a 1.5-litre three-cylinder unit producing 107bhp. However, while the other engines are revised versions of the existing turbocharged 2.0-litre unit, they all bring more power and better efficiency. The 118i will be the entry-level edition in the UK, with 134bhp and CO2 emissions of between 134g/km and 125g/km, depending on your choice of gearbox and wheel size.
The 120i is the mainstream choice, with 174bhp, 184lb ft of torque and a 0-62mph time of 7.4sec (or 7.2sec with the eight-speed auto). Its CO2 emissions range from 136g/km to 133g/km. There's also the 125i, with 215bhp and 228lb ft of torque; it cracks 0-62mph in 6.4sec and returns CO2 emissions of 154g/km, or 148g/km with the auto 'box.
The front-end styling revisions were actually forced by the revised engines, some of which require greater cooling than before. The air intakes are larger as a result. BMW used this modification as an opportunity to alter the shape of the headlights, too; they're now more rectangular than before, with space for revised lens units.
The specs of the lights themselves will change, too. Even entry-level cars will get daytime running lights as standard, while the old optional xenon units have been dropped in favour of full LED set-ups. M Sport editions of the car will get LED headlights as standard.
The tail-lights are now more in line with BMW's family style, thanks to a shallower main unit and distinctive 'blades' that run in from the edges of the rear hatch itself. They also get LED technology as standard across the range.
The 1 Series' cabin gets more modest upgrades, including a piano-black finish to the centre console on all trim levels, chrome highlights on the radio and air vents and, in a throwback to BMWs of old, an analogue real-time fuel consumption gauge on models without a digital instrument panel.
All 1 Series will now get single-zone climate control as standard, with the option of a dual-zone system, and the infotainment system has also been revised. Even the entry-level Business stereo gets a power and torque display, while the range-topping Professional system can update its map data remotely by using its built-in SIM card.
Several optional features have been improved, too. For example, the self-park facility can now park the car into a side-by-side parking space as well as completing a parallel manoeuvre in a street.
Prices for the new 1 Series have yet to be announced, but only the most modest of increases over the existing versions is expected.
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