Originally the entry level engine was a 1.6-litre petrol with 102bhp, which is adequate but offers little excitement. However, in early 2008 a 1.4 TFSI model was introduced. This uses a turbocharger for perky performance, but its small size means it's more economical than the 1.6-litre unit. It's sporty too and provides great in-gear pace for overtaking.
The original 150bhp 2.0 FSI was replaced in 2007 with a turbocharged 160bhp 1.8 TFSI, which has strong mid-range acceleration and better economy. The 2.0 TFSI with 200bhp is shared with the 2005 Volkswagen Golf GTI and has strong performance as you'd expect. In terms of diesels, the entry-level engine is a 105bhp 1.9 TDI which offers decent performance along with impressive fuel economy of 55mpg - it's also available as an economy version (badged 1.9 TDIe) which emits 119g/km of CO2 and is capable of 63mpg.
This was replaced in July 2009 by a newer common rail 1.6 TDI which is far quieter and smoother. It's as quick from 0-62mph as the 1.9 TDI, taking 11.4 seconds, but economy is boosted to a very impressive 69mpg. The popular 2.0 TDI is available with 140bhp or 170bhp and both offer a great blend of economy and punch performance. Audi A3 performance is best with the charismatic 250bhp 3.2-litre V6 - fun, if you can afford the fuel bills, and very quick.
Transmission choices include a five-speed manual on less powerful models, or a six-speed on more powerful versions. Both shift smoothly, although the clutch pedal feels a little numb. Some versions have the option of DSG (double shift gearbox) which offers all the benefits of an automatic, with smooth gearshifts, plus the fuel economy of a manual. The DSG was re-named S-Tronic on Audis in 2006.
Apart from numb-feeling steering, there isn't too much to fault with the A3's handling. It turns in neatly and can be guided precisely on twisty roads. The limited body roll experienced when cornering is reined in further if sports suspension has been chosen from the options list (S-line and Sport models have lowered suspension as standard). More powerful versions without quattro all-wheel drive, such as the 170bhp 2.0TDI and the 200bhp 2.0T FSI can struggle to put their power down cleanly causing the front tyres to scrabble for traction.
The ride is good though - it's supple over all surfaces and cruises without complaint on the motorway. On fast A and B roads, it shows superb grip and has precise steering and a pleasing gearchange.