Offered with transversely mounted inline four-cylinder engines in both front and quattro four-wheel drive, the A3 was Audi's eighth model to have five valves per cylinder.

With this update, Audi's electronic stability control, traction-control, and brake force distribution systems became standard in some countries.

[6] Their evaluation concluded "the column lock, adjuster lever and bracket presented hazards in the knee impact area for the driver.

The S3's quattro system utilises a Haldex Traction coupling to adjust the bias of torque distribution from the front to rear axle as grip requirements change.

[7] Due to this, the S3 typically operates in front-wheel-drive in most conditions The S3 was sold in Europe, Japan, Mexico, South Africa, Australia, and New Zealand.

Options include a Bose sound system, boot/trunk or in-dash mounted 6-disc CD changer, metallic paint, 18-inch 9-spoke RSTT wheels, glass sunroof, centre arm rest, privacy glass (B-pillar backwards), auto-dimming rear-view mirror, parking assist, luggage net, heated front seats, cruise control, aluminium door mirror casings and part leather/Alcantara (blue/silver/yellow) combination seat coverings.

In 2005 the "S line" trim level, offering new decorative elements, became available and the three-door A3 received the same front-end styling features as the Sportback model.

For the first time, the A3 became available in the North American market, exclusively with the Sportback body, with the base 2.0 inline-four FSI introduced in 2005 as a 2006 model, and the 3.2 VR6 Quattro following.

The A3 Sportback is 80 mm (3.1 in) longer than the base three-door body, and includes improved rear cabin space and a larger luggage compartment (370 litres).

Offered in three- and five-door body styles, the second generation—Typ 8P—S3 is powered by a modified and uprated Volkswagen Group-sourced 2.0-litre turbocharged FSI petrol engine, with a maximum output of 195 kW (265 PS; 261 bhp).

The engine features uprated high-performance pistons, revised boost/fuel mapping, increased turbocharger size (KKK K04) and larger intercooler.

These include revised nose and tail styling, with a modified grille and daytime running lights, common rail 2.0 TDI engines, seven-speed S tronic dual clutch transmission availability for the smaller non-U.S. engines, and optional "magnetic ride" adaptive shock absorbers.

The chassis has Audi's Magnetic Ride Suspension system, lowering the vehicle 1.4 inches (36 mm) from the base model.

It also has ceramic front brakes, a four-link rear suspension and electro-mechanical servo assist for the rack and pinion steering.

[17] The Audi RS 3 is derivative of the A3 Sportback with a 5-cylinder, 2,480 cc (151 cu in) turbocharged engine rated at 340 PS (250 kW; 335 hp) and 450 N⋅m (332 lb⋅ft), vermicular-graphite cast iron crankcase, seven-speed S tronic transmission with two automatic modes and one manual mode, Quattro on-demand four-wheel drive system, widened track to 1,564 mm (61.57 in), MacPherson strut in aluminum, lowered body by 25 mm (0.98 in), 19-inch cast aluminum wheels in machine-polished titanium styling (optional black with a red rim flange) with 235/35 front and 225/35 rear tires, 370 mm (14.57 in) front and 310 mm (12.20 in) ventilated brake discs, aluminum brake disk covers, four-piston fixed calipers in high-gloss black with RS logos, electronic stabilization program with Sport mode, flared front fenders made of carbon-fibre-reinforced plastic (CFRP), prominent sill panels and exterior-mirror casings in matte aluminum, roof spoiler, high-gloss black diffuser insert, two elliptical exhaust tailpipes on the left, black interior, sports seats upholstered in Nappa leather with silver contrasting stitching, inlays in Piano black finish or Aluminum Race colour, flat-bottomed leather multifunction sports steering wheel, choice of five body colours are available with an unlimited selection of custom paint finishes.

It included Vienna leather upholstery, front seat heating, rear parking sensors, automatic headlight and wiper activation, cruise control, a Bluetooth mobile phone interface.

The "e"-model, Audi's equivalent of Volkswagen's BlueMotion, is available with the 1.9 L TDI engine, and offers a more ecological car, with a CO2 emission below 120 g/km.

First vehicle using the flexible modular Volkswagen Group MQB platform, the third generation is available as a three-door hatchback, a five-door "Sportback", a four-door saloon to directly rival the Mercedes-Benz CLA-Class, and a two-door Cabriolet.

[48] In Malaysia, the Audi A3 was launched in 2014 and sold as two models - a 1.4-litre with 7-speed S-Tronic automatic transmission, and a 1.8-litre with 6-speed DSG and Quattro all-wheel drive.

The synthetic methane was produced by waste product from a nearby Werlte biogas plant operated by power utility EWE.

The revised model featured the same battery and drivetrain as before, now rated at 22 miles of electric range under the new WLTP test.

It features new pistons with stronger bolts and new rings, as well as reinforced connecting rods with new mounts transferring the power to the crankshaft.

The cylinder head is made of a new lightweight aluminium alloy designed with high strength and temperature resistance in mind.

There were multiple updates on the interior as well, with a fully digital 12.3-inch instrument cluster screen placed behind a revised steering wheel available as an optional upgrade.

[citation needed] It shares the MQB evo platform with other Audi models, and with the Volkswagen Golf Mk8, SEAT Leon Mk4, and Škoda Octavia Mk4.

The S3 model has the same 2.0L petrol engine from the previous generation, producing 310 hp (231 kW) and 400 N⋅m (295 lbf⋅ft) of torque, but this time is only available with an automatic gearbox.

In the countries that will receive The PHEV A3 will no longer be called The e-tron because this name is reserved for electric Audi cars.

The highest specification RS 3 model is fitted with a 2.5-litre 5-cylinder producing 400 PS (294 kW; 395 hp) and 500 N⋅m (369 lb⋅ft), and has 0-60 mph (97 km/h) acceleration time of 3.8 seconds.

[74] This is partially due to the lack of a petrol particulate filter for US model cars, as it is not required to meet emissions standards.

After the release of 4th generation of Audi A3; the model of RS 3 LMS TCR is also changed, and it will firstly start to race in 2021 WTCR season.