Audi has confessed that the lowest-emitting version of its new A4 – the 112g/km 2.0 TDI 136hp – may not be the default choice for the fleet sector, despite its cleanliness and the associated tax breaks.

Speaking to BusinessCar, A4 product manager Hannah Fahlgren explained: “There are certain restrictions on things, like the wheel size you can have, and you can’t have a tow bar in order to maintain the emissions levels.” She added that the 2.0-litre TDI engine in 143hp guise, which emits 119g/km, is likely to be a more popular choice among business users because it allows for more flexibility in terms of specification levels.

The 2.0-litre TDI engine, which is also available with power outputs of 163hp and 177hp, is expected to account for 80% of A4 sales across the board. Diesel engines – including the two higher-powered 3.0-litre V6 units – are tipped to account for 85% of A4 sales compared to just 15% in petrol.

Audi has also introduced a new SE Technik trim level, which is designed to appeal to fleets. It adds Milano leather trim, satnav, an iPod connection and upgraded parking assistance over the standard SE and costs an additional £1100.

There had been speculation that the launch and on-sale date of the new A4 were timed to coincide with those of it’s chief rival, the BMW 3-series. Fahlgren said: “Rumours had it that we were going to see the car in quarter one of 2012 but we were working to our own deadlines, so it was just a coincidence.”