- See also Audi S4
The Audi A4 is an automobile series made by Volkswagen Group, first sold in 1995 as a 1996 model and replacing the Audi 80. It was originally based on the B5, the same as the current VW Passat, and had the same chassis until a redesign in 2002. One distinction was the combination of longitudinal engine orientation and front wheel drive. Four wheel drive was available as an option. It was at first only available with a 2.8 litre 172 horsepower V-6 until 1997, when the 150 horsepower 1.8 litre Turbo inline-4 was introduced. This engine was affected by an oil sludge problem.
In 1999, the sedan/Avant received a facelift with a revised engine — the 2.8 was changed from 2 valves per cylinder to 5 valves per cylinder (for 190hp). Also, new taillights, headlights, and minor interior changes were available the next year. A high-performance version, the Audi S4 was introduced in 2000. The S4 was equipped with a bi-turbo intercooled 2.7 liter V6, producing 250 bhp (186 kW) and 258 ft.lbf (350 Nm) of torque. The car came in both a 6-speed manual or a 5-speed Tiptronic transmission to drive the power to the wheels via Audi's 'Quattro' four wheel drive system. For 2001, the turbo boost on the 1.8T engine was raised to make 170 hp (127 kW). Cars with the boosted four get a red "shadow" under the letter "T" on the back. Later models were available with power outputs of 163 or 190 hp (122 or 142 kW).
For 2002, the car was redesigned with a new chassis designated B6 (also called "8E" by Audi). It received a larger displacement engine, the 220 hp (164 kW) 3.0 V-6. The 1.8 T is still being produced. A continuously variable transmission was an option on front wheel drive cars. The new Audi S4 was introduced in 2003 and still used up to the current (2005) model. The new S4 is powered by a 4.2 liter 40-valve V8 engine producing 340 bhp (254 kW). New to the 2003+ model S4's are the choice between a 6-speed manual or new 6-speed Tiptronic gear box.
Other engine include a 1.9 I4 turbocharged diesel TDI with 100 or 130 hp (75 or 97 kW) and a 2.5 TDI V6, producing in its early incarnations 155, but presently 163 or 180 bhp (122 or 134 kW), depending on the model. The diesel engines are not available in the United States.
The biggest competitors for the A4 are the BMW 3-series, the Mercedes-Benz C-Class and the Lexus IS 200/300. The original A4's sucess is generally viewed as the single most important factor for Audi's recovery in the US after the sales plunge caused by the Audi 5000's sudden acceleration incidents (disclosed on the TV program "60 Minutes" in 1986). Early A4s also suffered from several widely known major design flaws, such as premature control arm and timing belt failures.
The latest model changes introduce a whole raft of new features to the range, and include the introduction of the 2.0 Turbo FSI, 3.0TDI and 2.0TDI engines.
Awards
The A4 made Car and Driver magazine's Ten Best list for 1996 through 1998, and again for 2002.
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