"2000 S4 purchased as certified pre-owned in 03 at 58k mi., currently at 110k. Stock condition.
This car has excelent perfomance, styling and comfort. Its biggest down falls are common to almost all Audi/VW products of its era, especially the VW Passat which is an Audi in disguise. These issues are: electronics failures, oil leaks, short control arm life, and labor intensive and relatively frequent timing belt/water pump replacements. This is probably not the car for you if you don't do any of your own maintenance. I do my own minor services to save on costs and have a mechanic friend for big jobs. I source parts from on-line suppliers for lowest cost and better availability. I also purchased an aftermarket Audi/VW specific computer interface. Common Audi issues this car has had:
* ABS controller failed, replaced with re-manufactured unit.
* Coolant temp sensor failed,
* Coolant expansion tank cracked and dripped coolant.
* Mass Air Flow Sensor failed
* Bose Speaker failed
* Vacuum Vent Valve Switch failed (on clutch peddel, stops over-acceleration with clutch in)
* Digital display in center of instrument cluster failing.
* Oil seal oil leaks: valve covers, twin-cam chain tensioners and upper oil pan.
* CV-joint boot failures (common to all FWD AWD cars).
* Four link/four ball-joint front control arm design is hard on the ball joints and bushings leading to failure to hold the wheel alignment when adjusted. Complete link set replacement is recommended.
* Dealer installed OEM water pump leaked after only 35K mi, resulting in an early re-do of the 70k to 80k mile timming belt/water pump service. This is a big job that requires dissasembly of the "lock carrier" for access. That's the support structure that holds the radiator, fans etc. The parts from the front of the fenders forward have to be removed to access the front of the engine. (Yes, I said removed!) The A4. A6, A8 and VW Passat are the same. Also OEM water pumps use a plastic impellor that is prone to failure. Look for an aftermarket pump with a metal impellor when replacing the pump. Also very important for the mechanical life of the turbo engine use only synthetic oil. Use A VW502 spec compliant synthetic 5W-40 oil if you can find it. It is not commonly available at most auto parts stores in the US.
Know what you are getting into, otherwise its a blast to drive! This car is my second Audi, it replaced an '87 4000 CS Quattro."
"Wow! my 2000 Audi S4 is so amazingly FAST! The twin turbo 2.7 L V6 in this small 4 door sedan delivers amazing performance. I love the handling. Sport suspension really performs around every corner, but is a bit rough. The seats are not very comfortable for long road trips. I mostly use mine for short commutes racing around town. Love it when muscle cars think they can take me, big surprise when the light turns green :) Find a good audi/VW mechanic, don't bother with the dealerships for service if yours is past the warranty."
"This is by far the best car i have ever owned, even though people say repair costs are ungodly expensive thats just not true! Nothing that i have replaced on the car has seemed like it was over priced at all. This is an amazing car and i absolutely love everything about it!"
"This car is perfect for nearly everyone, from the daily commuter to the race car fanatic. Though it has four doors, I wouldn't recommend rear passengers too often. The rear seat is a bit cramped. Perfect for a childs seat. It drives like it's on rails and is by far the safest car I've owned. Highly recommended"
"Bought my 01 S4 in 2005 with 33k miles on it. This car handles great and accelerates quite nicely. The all wheel drive is unmatched. If you began to slide in the snow it would immediately correct me. Only the roughest power slides would evade the AWD system. Ran great for a time, but lots of repairs. Averaged 1 major repair per year."