WHEN the new Audi A4 saloon and Avant hits the streets later this year they will come with the promise that drivers will enjoy a truly hi-tech experience.

Don't be surprised though if you can't spot much difference from the current A4 saloon and estate variants.

But then Audi doesn't tend to do radical design revamps - when you have a winning formula there's little point changing for changing's sake.

What A4 fans will appreciate are things like a lighter weight than the outgoing models which, says Audi, makes the new cars up to 21 per cent more fuel efficient.

They may also quite fancy technology options like the Audi virtual cockpit, help in traffic jams, assistance for avoiding collisions and safe turning, while there's also a new smartphone interface which supports Apple CarPlay and Android Auto.

Beneath the bonnet is a choice of seven engines - three TFSI petrol and four TDI diesels.

Their power output has increased significantly and ranges from 150PS to 272PS, but fuel consumption is cut and CO2 emissions dip below 100g/km in the 2.0 TDI ultra Saloon.

The powertrain and the chassis of the new Audi A4 and A4 Avant estate have been redeveloped and in the case of the cars' automatic transmissions there's now a fuel-saving freewheeling function.

As for luggage space, the Avant boasts a capacity of 505 litres, the highest in its area of the market, and with the rear seats folded down and loaded to the roof, the volume rises to 1,510 litres.

Standard kit includes 17-inch alloy wheels, xenon headlights with LED daytime running lights, the smartphone interface, keyless go, Bluetooth, Audi drive select, a 7-inch MMI colour display and three-zone climate control.