New details are starting to emerge about the 2014 Audi A4 (B9).

A recent report suggests the car will ride on the MLB Evo platform which will enable it to weigh 120 to 150 kg (265 to 331 lbs) less than the current model. Despite the reduced mass, the A4 is expected to grow in size to battle the enlarged BMW 3-Series.

Engine options are still a closely guarded secret, but the TDIs are expected to produce 150 to 300 PS (110 kW / 148 hp to 221 kW / 296 hp). Likewise, the petrols should develop 150 to 350 PS (110 kW / 148 hp to 257 kW / 345 hp). To improve efficiency, the models will reportedly be outfitted with an engine stop/start system, brake energy regeneration and a thermal energy recovery system.

If that doesn't sound eco-friendly enough, the A4 plug-in hybrid is rumored to have a rear-axle electric motor that will enable the car to travel 30 to 60 km (19 to 37 miles) on electricity alone. Additionally, this setup will offer an all-wheel drive system dubbed e-Quattro that will have no mechanical connection between the axles.

Last but not least, there's word of a CNG variant that will be launched as part of Audi's e-gas project.

Click title for the source