Which used Audi A4 saloon should I buy?
You'll need a good reason not to consider the diesel models. The 2.0-litre TDI engines, with between 118bhp and 168bhp, are the best option - not only for availability, but for running costs and residual values, too. There's also a 2.7-litre with 187bhp and a CVT automatic gearbox and a quattro four-wheel-drive 237bhp 3.0-litre. There is no auto option on the 2.0-litre engines, but the 3.0 is also available with an S-tronic semi-auto gearbox.
The petrol versions start with the excellent 1.8-litre turbo, with between 118bhp and 158bhp, and a 2.0-litre version with 208bhp. Both are available with a CVT automatic gearbox. The four-wheel-drive 261bhp 3.2-litre is more of a car for keen drivers, but is rare on the used market.
Entry-level specification is good, with stability control, electric windows all round, climate control and remote central locking, while SE adds alloy wheels, parking sensors, upgraded stereo and interior trim, plus multi-zone climate control. The S line version sits on lowered sports suspension, gets larger alloys, and sporty cabin trim and a body styling kit.