Background notes on the Audi A4

The Audi A4 is on its eighth generation.

All nine of the turbo charged and directly injected engines that power it are linked to start/stop and recuperation systems.

The A4’s petrol engines begin with the 1.8-litre TFSI with 120PS. There’s also a more powerful 1.8-litre TFSI which includes many innovations - including control of the valves and their lift, thermal management, fuel injection, turbocharging and the integration of the exhaust manifold.

Power has been increased from the previous 160PS to 170PS, with torque boosted from 250Nm to 320Nm.

It combines 49.6mpg average fuel economy with carbon dioxide output down from 169g/km to 134g/km.

With the departure of the 3.2-litre naturally aspirated V6 petrol engine from the latest range, the 2.0-litre TFSI unit with 211PS completes the petrol line-up. Anyone still wanting the 3.2 V6 will be resigned to used Audi vehicles.

There are six TDI engine options employing either four or six cylinders. Of the four 2.0-litre four-cylinder units, two power efficiency focused TDIe models. The 136PS version which performed this role originally continues, and has been joined by a 163PS version. Carbon dioxide emissions drop to 112g/km from 120g/km in the A4 2.0 TDIe 136PS, and the 2.0 TDIe 163PS runs this figure close at 115g/km. Combined cycle economy figures stand at 65.7mpg and 64.2mpg respectively.

The 143PS version of the 2.0-litre TDI continues alongside a 177PS unit – with power up from 170PS – that heads the four-cylinder line-up. The 136PS, 163PS and 177PS units have a new pendulum-type absorber in the dual mass flywheel.

In the V6 camp, a 204PS 3.0-litre unit first seen in the A6 Saloon and A7 Sportback is adopted in place of the 2.7-litre TDI in front-wheel-drive models. A 245PS version is linked exclusively to quattro all-wheel-drive in Saloon, Avant and allroad quattro variants.

A six-speed manual transmission is standard for Saloon and Avant models with front-wheel drive, and most variants offer the continuously variable multitronic automatic transmission as an option. The quattro versions feature either the manual transmission or the seven-speed S tronic twin-clutch automatic. The A4 allroad quattro employs a manual transmission or S tronic with all engine versions.

A thermal management system shortens the warm-up phase of the manual transmission reducing friction losses.

The quattro permanent all-wheel-drive system is standard for the A4 allroad quattro and 245PS A4 3.0 TDI quattro models.

The A4 family uses the self-locking centre differential, which under normal driving conditions transmits torque to the rear wheels in the ratio of 40 to 60, but can rapidly vary this according to the situation. Torque vectoring supplements the work of the centre differential with intermittent brake applications to boost handling precision.