The origins of the first Audi 100 have become legendary in Germany. When Volkswagen purchased Auto Union from Mercedes Benz in 1965, they seem to have been motivated by a desperate shortage of production capacity for their ’Beetle’ model which at that time was selling faster than the cars could be produced. The then nearly new Auto Union plant at Ingolstadt, built under Mercedes ownership and control, was quickly adapted for Beetle assembly: Volkswagen boss Heinrich Nordhoff, mindful of the poor sales record of the DKW F102, and at a time when the new Audi F103 had yet to prove itself in the market place, gave instructions that no further new Auto Union (including Audi) models should be developed.
However, it was not just the Ingolstadt manufacturing facility that Volkswagen acquired from Mercedes when they purchased the Auto Union business. Among the employees inherited from the Mercedes era was engineer Ludwig Kraus. Kraus did not share Nordhoff’s apparent conviction that demand for the Beetle would remain insatiable for ever, and it was Kraus who developed the Audi 100, in direct contravention of instructions from Volkswagen management, and in secret. The first Nordhoff knew of the project was when he was presented with a production ready prototype. It is to Nordhoff’s credit that he changed his mind and gave the car the green light. The Audi 100 would be a commercial success, but it would also be the first of a series of front engined water cooled Audi based designs from the Volkswagen group that would, starting with the first Passat in 1973, enable the group to survive and flourish once the European and US markets began to lose their appetites for rear engined air cooled models.
The Audi 100 was shown to the press on 26 November 1968. It's name originally denoting a power output of , the Audi 100 was the company's largest car since the revivial of the Audi brand by Volkswagen in 1965. The C1 platform spawned several variants: the Audi 100 two- and four-door saloons, and the Audi 100 Coupé S, a stylish fastback coupé.
Audi followed up the introduction of the four-door saloon in November 1968 with a two-door saloon in October 1969 and the 100 Coupé S in autumn 1970. The cars' four-cylinder engines originally came in base (1.8 litre, ), 100 S (1.8 litre, ) and 100 LS (1.8 litre, ) guise, while the Coupé was driven by a bored-out 1.9 litre developing . From April 1970 the 100 LS could be ordered with a 3-speed automatic transmission sourced from Volkswagen.
Starting with model year 1972 the 80 and 90 PS versions were replaced by a new regular-petrol-variant of the 1.8 liter engine developing 85 PS (84 hp/63 kW); at the same time, the 100 GL was introduced that featured the 1.9 liter engine formerly used in the Coupé S only.
In September 1973 the 100 received a minor facelift with a somewhat smaller grille and reshuffled taillight lens patterns. The rear torsion bar was replaced by coil springs.
For model year 1975 the base 100 was re-christened the 100 L and received a 1.6 liter four cylinder engine (coming out of the Audi 80).
The C2 Audi 100 was launched in 1976, with crisper styling and an unusual five-cylinder engine (the first gasoline 5 in the world — Mercedes-Benz had shown the way in 1974 with their three litre diesel 5-cyl in the Mercedes-Benz C111). It was initially a 100 bhp (74 kW) engine offering "6-cylinder power and 4-cylinder economy", and later upgraded to 136 bhp (100 kW).
Engines available included:
About 850.000 Audi 100/200 C2 were built, of which 133.512 were sold in the USA.
Edging out the Ford Sierra as Car of the Year in Europe, the 1983 Audi 100 had a remarkable aerodynamic look, achieving a drag coefficient of 0.30 for its smoothest base model. The increased aerodynamic efficiency resulted in better fuel economy and consumers all over the world were waking up to this fact. This became a great marketing tool for Audi in the 1980s, and marked a huge leap forward from the boxy shape of the C2, as well as the technology it introduced, including the procon-ten safety system.
Audi was able to catch up to modern smooth look first seen in this sector on the 1975 Citroën CX. The Audi in turn influenced the Ford Taurus, an American-made sedan from 1986. This rounded look became the norm by the 1990s. It also set a styling trend of flush wheel covers, a thick black side door moulding and blacked out window frames eventually adopted by a range of cars from the 1984 Honda Accord to the K cars. Audi innovated flush windows on the C3, a key area for aerodynamic drag that has been adopted by virtually all manufacturers today.
The two-door models were no longer available, and the Audi 100 Avant was reintroduced as Audi's first attempt at a station wagon based on the 100. The 200 continued as the upmarket variant with several versions of the 2.2l turbo 5 cylinder available in different markets over its life ranging in power outputs from 121 kW (165 bhp) MC engine, through the 136 kW (180 bhp) and 147 kW (200 bhp) versions to the final 162 kW (220 bhp) 20-valve 3B engine available from 1990. The 200 20V was distinguished by its flared front and rounded rear wheel arches instead of the flat type used for the rest of the 100-200 range. The MC turbo engine was available in the 100 as well for some markets.
The 100 also featured a breakthrough diesel engine, one of the first to use direct-injection in the turbo-diesel model.
In the United States, the 5000 name was abandoned after Audi received very negative publicity over its "unintended acceleration" incident, a problem exacerbated by a November 1986 CBS News' 60 Minutes program., The National Highway Traffic Safety Administration (NHTSA) concluded that the majority of unintended acceleration cases, including all the ones that prompted the 60 Minutes report, were caused by driver error such as confusion of pedals. CBS issued a partial retraction. A legacy of this are the intricate patterns many shifters use, and brake interlock mechanisms to prevent inadvertent shifting into forward or reverse, where the standard was a straight front-back pattern.
However, with the damage to its US reputation done, the 5000 once again became the 100, or the 200 depending on engine configuration, for the 1989 model year. Audi sales in the US would not return to the same level for 15 years. During its last year of production for the 1991 model year, the 100 and 200 featured a larger, more rounded rear wheel-well opening. This minor styling revision was something of preview of the styling of the upcoming fourth generation model that was waiting in the wings and, in appearance, further dissociated the model from that of the 5000 with its damaged reputation.
The engine range comprised the following engines:
Audi 5000/100/200 North America:
At the end of the decade, the Audi V8 was announced. This was essentially a 200 quattro with an engine derived from two four-cylinder Volkswagen Golf GTI engines put together. Although styling was similar to the 200 on which it was based, with the exception of the roof and doors, body panels were NOT shared. The V8 was available as a 3.6 L or a 4.2 L engine. It was the first quattro model to have an automatic gearbox, featuring a ZF 4-speed unit with a viscous coupling centre differential, combined with a Torsen rear differential. The manual gearbox quattro's across the range continued with a conventional rear differential, and the Torsen centre differential.
A heavily revised C3, the C4, was introduced in 1991. The C3-platform V8 continued to be sold as a separate line. The major change for the C4 was the introduction of a 2.8L, 90 degree, SOHC, 12v, V6 engine. It was later joined by a 2.6L variant, though this is actually a 60 degree engine. They are essentially the same engines offered in the 1992, B4 Audi 80. The option of quattro permanent four wheel drive was an option across the range, and the Audi 100 quattro was available with a ZF 4-speed automatic gearbox.
For the 1995 model year, Audi dropped the 100 nameplate, renaming it the A6 instead. In addition, what had previously been sold as the S4 became the S6, however the two models became completely independent of each other after Audi's replacement of the 80 with the A4 model, also in 1995. The V8 was eventually replaced by the A8 in 1994.
The actual Audi 100 design continued until early 1997, when it was replaced by an all-new A6.
The C3-platform Audi 100 was also produced in Changchun, China, by FAW (First Automobile Works, a Chinese automotive manufacturer), for many years during the 1990s. Since most products are for governmental usage, all of China-made 100s are front-wheel drive sedans with a 2.0l 4 cylinder engine or a 2.3l 5 cylinder one.
In 1990, Political Bureau of the Central Committee of the CPC approved a resolution to circumscribe car import and the engine displacement of cars equipped to officials. Furthermore, the resolution also prescribed that all cars of central departments of both Party and government must be homemade ones. As the most luxurious and advanced cars made in China in early-1990s, FAW-Audi 100 and 200 have possessed a considerable percentage in Chinese high-class market of executive cars for nearly one decade, until the C3-platform cars was replaced by Audi A6 in 1999.
During the negotiation between FAW and Volkswagen in late-1980s, Volkswagen acceded to FAW's suggestion of combining the C3 platform with previously introduced Chrysler engines in the new generation Hongqi (Red Flag). Hongqi CA7200 series with the technology of C3 were launched in mid-1990s, while most of C3 Audi 100 parts could be made in China. CA7200 were initially equipped with Chrysler 2.0l or 2.2 l 4 cylinder 488 engines, whose product line was introduced into China in 1987. In 2000s, new Nissan VQ20 engines replaced the original 4 cylinder petrol engine.
In late 1991, Audi unveiled the second Duo generation - likewise based on the Audi 100 Avant quattro. Once again this featured an electric motor, a 28.6 bhp three-phase machine, driving the rear wheels. This time, however, the rear wheels were additionally powered via the Torsen differential from the main engine compartment, which housed a 2.0-litre four-cylinder engine.