Curbside Classics: 1990-1997 Audi 100 & A6 (C4) – Everything Is Fine

When it came to replacing the third “C3” generation of its midsize 100/200 (a.k.a. Audi 5000) line of vehicles, Audi certainly had its work cut out. Boasting dramatic aerodynamic styling, flush side glass, spirited engines including a 220-horsepower 20-valve turbo I-5, features such as ABS, the availability of Audi’s Quattro all-wheel drive, a stunning fastback Avant wagon, and overall proficiency in efficiency, the C3 was a highly successful model — notwithstanding the blemish of U.S.-market 5000’s later debunked unintended acceleration scandal. Although it was a tough act to follow, after a decade on the market, the C3 was due for a replacement. In true logical German fashion, enter the appropriately-codenamed Audi C4.

In the time since the C3 debuted, Mercedes-Benz soon released its massively successful W124 (Ur-E-Class) and BMW rolled out a new highly technologically-advanced generation (E34) of its 5 Series. More significantly, particularly in North America, was the introduction of three new luxury brands and executive-class sedans from Japan, in the form of the Acura Legend, Lexus LS 400, and Infiniti Q45. The luxury-sports sedan market was more saturated and competitive than ever, and Audi had an especially difficult challenge. Not only did Audi need to build a worthy successor to the C3 and a competitive entry towards rivals, but it also had to build a mainstay model that would restore its presence in the U.S., where brand sales had plummeted over 80% in just 5 years following the fraudulent yet severely damaging unintended acceleration scandal.

Introduced in 1990, the C4 generation Audi 100 (as all were now called) was in many ways a careful evolution of the C3. Styling and proportions of the sedan followed the template of the C3, with long hood, six-window greenhouse, and upright trunk. Versus the C3’s very rectilinear lower body styling, the C4 exuded a more sculpted look overall, though retaining the C3’s basic profile and footprint.

In fact, C4 sedan body exterior dimensions were all within millimeters of its predecessor. Versus the C3, however, engineers widened the track by two inches for greater stability, not to mention a visually more athletic stance. Audi was also able to stiffen the chassis by some 30%, add larger front and rear stabilizer bars, add larger four-wheel disc brakes, all while giving the C4 100 two more cubic feet of interior volume, in true German efficiency.

Unlike the sedan’s styling, the styling of the C4 Avant (as all future Audi wagons would be known as) was a dramatic departure from its fastback predecessor. “Undramatic” might be a better way to describe it, as the C3’s radical Citroën-esque profile was traded for a more conventional two-box wagon design.

Nevertheless, the C4 Avant was a very handsome wagon, still possessing a hint of fastback roofline and somewhat defined sedan boot for a sportier look than midsize wagons from Mercedes-Benz and Volvo. Running on the sedan’s good looks, the C4 Avant boasted an additional 48 cubic feet of cargo volume for a total of 64.4 cubic feet. Additionally, the Avant offered a flat-folding rear-facing third row bringing total passenger capacity to seven if needed.

Bigger news came from under the hood, in form of a new 2.8-litre 12-valve SOHC V6. Producing 172 horsepower and 184 lb-ft torque, this new engine offered a substantial output increase over the outgoing C3 100’s 2.3-litre I5 that made 130 horsepower and 140 lb-ft torque. This engine served was standard on North American-spec 100s, while European-spec 100s were also available with a plethora of inline-4s and inline-5, both petrol and diesel.

Of course, even more exciting for enthusiasts was the performance-minded Audi S4 (a.k.a. Ur-S4) variant. While not quite a BMW M5 in terms of power, the S4’s standard 2.2-liter turbocharged I5 produced an impressive 227 horsepower and 258 lb-ft toque for zero-sixty times of 6.2 seconds. Combined with its standard Quattro all-wheel drive, and upgraded brakes, wheels, and tires, the Ur-S4 was a formidable German luxury high-performance sedan, even more so in Europe, where one could spec the S4 with a 4.2-liter V8.

Using a MacPherson strut front suspension with firm tuning, front and rear stabilizer bars, and speed-sensitive power rack and pinion steering, the C4 gave its driver and passengers a ideal balance of precise, engaging German handling coupled with a smooth, comfortable ride well-suited for long journeys. This “best of both worlds” balance of ride and handling is one of Audi’s strengths in its cars today.

As with before, the 100 was available in either front- or all-wheel drive, with the latter using Generation II of Audi’s Quattro. Used in the C3 100 from 1988 until the end of production, this permanent all-wheel drive system used a Torsen center differential with a default 50/50 split and the ability to send up to 75% of torque to either axle. Quattro cars also upgraded the rear suspension to a fully-independent trapezoidal arm setup over the front-wheel drive’s semi-independent torsion beam rear suspension.

Whereas European C4s offered Quattro with most available petrol engines, in North America, Audi limited availability of Quattro exclusively to the top-trim 100 CS for a $3,000 price premium over front-wheel drive 100 CS models and an $8,000 entry price over the base front-wheel drive 100.

Much like the exterior, the C4’s interior was a clear evolution of the C3’s, to an even greater extent at that. However, by no means was this drawback, as the C4’s interior was a model of aesthetically pleasing and ergonomic excellence that was typical of German car interiors of the day. Maybe it’s just me, but doesn’t that tidy stack of physical buttons and comprehensive set of analogue gauges look so refreshing compared to the plethora of digital display screens and touch screens that occupy the majority of modern cars’ dashboard real estate?

Furthermore, in the increasingly competitive field of midsize luxury sedans, Audi took care in enhancing the luxury aura of the C4’s interior. The quality of plastics was improved with more soft-touch surfaces, while the appropriate use of real woodgrain trim was changed from a visually harsher Zebrano, to a softer, warmer high-gloss Canadian Elm for increased elegance and the added benefit of less damage to tropical rain forests.

Base C4 100s and A6s continued offering supple velour with an attractive vertically-striped pattern as their featured standard upholstery, while leather was naturally an upgrade. S4/S6 models featured even racier seats with thicker side bolsters and extendable thigh cushions.

Perhaps the most interesting aspect about the Audi C4 was its mid-cycle facelift in 1994, which resulted in it gaining a new name and new identity. Now called the “A6” to fit in with Audi’s new nomenclature, visual changes included a new chrome-trimmed grille, ellipsoidal projector-beam headlights with clear turn signals, chrome shadow line trim around the side windows, new taillight clusters, new wheel designs, solid outboard headrests, and body-colored lower trim. Overall, little else was actually changed beyond minor styling details, but somehow the A6 conveyed a smoother, more grown up, and more elegant look compared to the 100.

At least in North America, the A6 also presented somewhat of a better value proposition, specifically pertaining to all-wheel drive, which could now be had at a much lower entry price. Audi kept base prices for the 100 and A6 relatively constant through the years, though with the A6, Audi eliminated the 100’s base, S, and CS trim levels in favor of one reasonably-equipped A6 model with a number of available options and packages.

Whereas the 100 required the top-trim CS with nearly every option in order to add Quattro for almost $44,000, the A6 offered all-wheel drive as a standalone extra-cost option. Thereby, one could get an A6 Quattro — sans leather, dual power front seats, heated seats, sunroof, remote keyless entry, and automatic transmission — for around $32,000.

Nonetheless, it wasn’t until the C4’s C5 generation successor arrived in 1997 that the A6 really began turning heads and gaining serious momentum. Quite possibly the most dramatic Audi restyle ever, the C5 was the car that showed the world Audi was firmly one of the big boys.

With this in mind, nearly three decades after its debut, it’s important that we not under-credit the C4’s significance for Audi. From a global perspective, the C4 100/A6 was the backbone that kept Audi going throughout the early-to-mid 1990s. As it relates to the North American market, the C4 was the car that kept Audi alive, accounting for as much as 70% of total Audi sales.

Following the unintended acceleration scandal and its subsequent plummet in sales to less than 15,000 units annually, Audi could have easily gone the way of other European marques such as Peugeot, Renault, and Alfa Romeo, all of which retreated from the North American market in the late-1980s/early-1990s. While not nearly as revolutionary and noteworthy as its C3 predecessor nor its C5 successor, the C4 played an important piece in the very possibility of Audi’s future, and its rise to becoming one of the world’s top-selling luxury brands, reaching nearly 1.9 million units sold in 2017.

In many ways, the C4 was a transition car for Audi, bridging the gap between quirky premium brand and elegantly understated luxury brand. Solidifying this foundation, I can’t help but describe the Audi C4 with a phrase I picked up in my travels to Germany, “Everything is fine”. In the somewhat straight to the point German demeanor, it’s a phrase an English-speaker may use in the place of “Don’t worry”, and I think it’s a very fitting way to describe this car.

1993 Audi 100 CS photographed in Hanson, Massachusetts – July 2018

1997 Audi A6 Quattro photographed in Lower Manhattan, New York – March 2018

1997 Audi A6 Quattro Avant provided by Jim Klein – September 2019

Related Reading:

1993 Audi Ur-S4   (Jim Klein’s COAL)

1995.5 Audi S6 Avant   (Jim Klein’s COAL)

1987 Audi 5000 CS Quattro

1993 Audi 90 Quattro