Faults:

Rear suspension control arm bushing squeak at 50,000 miles. Replaced under Audi Assured used car warranty.

Auxiliary water pump leak (supplies coolant to the turbocharger after engine shutoff), at about 60,000 miles. Drove with it for about 3,000 miles, easily diagnosed and replaced.

Clutch slave cylinder blew at about 65,000 miles, disabling the clutch pedal and rendering the car undrivable. Made the mistake of taking the car to the dealer after the warranty expired (see below).

The nut securing the clutch pedal rod to the clutch master cylinder was left inadequately torqued by the dealer service department, working loose in a few hundred miles and stranding me with no clutch in rush hour traffic. After the dealer rectified the problem, I found a good independent garage for all further work.

Timing belt, water pump, and thermostat replaced at 75K. A regularly scheduled maintenance item, costing $1500 (ouch).

Windshield washer check valve clogged at about 90,000 miles, stopping fluid flow.

Coolant check valve leak at > 100,000 miles. $5 part, several hundred dollars to replace.

Power stage output relay burned out at about 105,000 miles, causing the engine to run on only three cylinders. Common problem with these cars. Drivable, but with terrible vibration.

Heater control servo motor seized at about 110,000 miles, in the middle of winter, resulting in no heat.

A front strut leaked its fluid at about 115,000 miles. Replaced both front struts with Bilsteins, which were better than the original Boges.

General Comments:

A conservatively styled luxury/performance sedan with everything that a buyer in this class could want during the 1990s: 227 HP turbocharged engine, with 360 HP easily available with off-the-shelf aftermarket kits; Quattro all wheel drive; deeply bolstered sport seats; glove-soft Nappa leather; wood-trimmed dashboard and doors; front and rear heated seats; automatic climate control; Bose sound system with 6-disc CD changer.

Performance was excellent. The engine had no "turbo lag" or sensation of the turbo kicking in, because boost started at barely above idle (1950 rpm). It was a bit sluggish off the line, and below 3000 rpm, but once you got rolling and used the gears, the car FLEW. Quattro allowed you to put down the power in any weather and road condition. Handling was stable and secure in all situations. The steering was too light and very numb on-center as stock, but simply removing the Servotronic variable-assist relay made the steering perfectly weighted and accurate. The brakes were criticized by some reviewers at the time for being small and fade-prone, and upgrades are available, but I never saw the need for street driving.

Gas mileage was disappointing. Mixed city and suburban driving, with no rush hour traffic (I used the subway for commuting while I owned this car), I usually got 17-18 mph. 100% highway trips returned no better than 24 mpg. A fairly large and heavy body, all wheel drive, turbocharging, and fairly low gearing (about 3000 rpm at 70 mph) was not a combination for high gas mileage.

The interior was a great place to spend long road trips. The sports seats, with their deep side bolsters, firm padding, adjustable lumbar support, adjustable thigh support, and 6-stage adjustable heaters, were incredibly comfortable on long journeys. Even the armrests were exceptionally well positioned, and tilt-adjustable in the center. The only criticisms that I had regarding comfort and convenience were weak A/C in the summer (the heater was very strong, on the other hand), the in-trunk position of the CD changer, and complete lack of cupholders aside from two soda can-sized cutouts that were added as an afterthought to the center console (and were blocked by the center armrest if it was lowered).

The many mechanical problems that I listed above were the only disappointment that I experienced with this car. The car's engine, body (which has a 100,000 mile rust warranty - mine had no body or underbody rust at all after 10 years and 125,000 miles, with a lot of winter driving), and interior materials were very solid and durable, but "small" mechanical part failures piled up once the car passed the 100,000 mile mark. Each repair involved parts that did not cost much, but required hundreds of dollars of labor to get to and replace. As a result, at this point (2008), I can recommend this car only if you find an exceptionally low-mileage example, or have the ability and time to do most of your own repairs. If either applies to you, I recommend the car wholeheartedly - it is an excellent performance sedan that is available at bargain prices now.

Faults:

Slow oil leak - still to be fixed.

Ignition (barrel) beginning to give some problems - a known issue - key sticking in barrel, for instance.

Coolant leak - broken seal, cured.

General Comments:

Great car - best I've owned so far. Quick, secure, safe, properly built. Interior very comfortable, clear dials, quite spacious. Boot is shallow, but deep.

MPG is tough - best I've ever got is 35mpg on an extended run. Around town it's looking like mid teens, week in, week out it's 21mpg. Also lots of stuff going on under the hood - hoses, seals, fluid lines everywhere. These things can and do go wrong having an Audi specialist nearby (I guess) would help.

I think this is a real eye-catcher of a car, in platinum silver with 17inch AVUS alloys it still holds its' head up with current BMW's, Audi's, etc. Very good value in the UK at the moment (2006).

With a good mechanic and being able to live with the mpg the S6 is a wonderful car to own.