I am debating picking up a 2004/2005 S4 Avant to replace my current DD ( '05 WRX Wagon). The Subaru has been very reliable thus far and while it should be just about as fast as the S4 (with my modifications and it being 600+ lbs lighter), it doesn't have the same well-constructed, higher-end feel.

My primary concern is maintenance. I want the S4 to be reliable and Audi's are known by many to be maintenance monsters. My only experience is with my brother's '96 A4 which had its share of problems.

Whatever S4 I buy would likely have somewhere in the neighborhood of 80k miles (to stay within my budget)...is buying a 5 year old S4 with 80k+ miles a terrible idea if I want to avoid headaches?

I would love any owner's feedback from those who own B6 S4s.

Thanks.

 

While I can't speak from direct experience, I can comment on what I've read about the 05/06 S4's.

Unlike other model year S4's you don't have to deal with turbo's blowing up or the extra maintenance cost of troubleshooting boost issues etc. With the V8 these cars run you should be concerned about a couple issues. The first I came across is excessive oil use, ie. burning of oil. I've also read that some owners have had catastrophic engine failures where the underlying cause has been unknown.

The primary thing I would look for in buying a used S4 with 80k+ miles would be documented maintenance records and a low number of owners. Both of these will indicate that the car has been reliable enough to maintain that long and is hopefully up to date in all it's maintenance. Beyond the oil consumption issues there's the simple fact that the V8 is thirsty.

Good luck with your search, I'm actually in the market for a new/newer car myself and may pick up a used S4 if the right on pops up.

 

only real problems with the v8 is the carbon build-up, before you buy it make sure the previous owner has done a carbon cleaning, or be prepared to shell out a few grand for the dealer to clean your valves and manifold.

 

I've heard about that. Is that something known only by "enthusiasts" or those on forums? The reason I ask is because it seems lots of the Avants out there were driven by someone's wife or were left totally stock and never really messed with which would lead me to believe these owners would simply cope with the car getting slower (as carbon increases).

Is there a service bulletin about it or a recommended procedure @ a certain mileage per Audi for taking care of this?

The other issue I know of can be the timing chain tensioner (and chain itself) at or before 100k miles or so....

Any additional feedback would be excellent.

 

None of the problems that have been mentioned in this thread are widespread. One of them doesn't even pertain to the S4, only the RS4.


Carbon Buildup: The RS4's direct injection FSI system has a side effect of having carbon build up on the valves and on the intake side of things. This is due to the setup of the direct injection and how the PCV system functions. All direct injection engines are suffering from this in some form or another. The 2.0T audi engines have it, the N54 in the BMW 335 is having it show up, and the RS4 has it. It is NOT an issue on the 340HP 40 Valve V8 in the S4 from 2004-2009.

Plastic Chain Guides: The internet has a fantastica way of making a VERY small problem seem like the sky is falling. Since very few people ever post on a message board to say "hey, my car is working great and I'm getting reliable miles from it" you usually only hear about problems. An incredibly small amount of engines have had issues with the timing chain guide tensioners failing and the engine failing as a result. Just like a timing belt, if the chain fails is a full on engine failure. However, the number that have failed is almost insignificant. It is so low in fact that none of the audi techs I have talked to, or met have ever seen an actual issue with one.

Since the chan guides are run off of the cars oil pressure they rattle when the car is started. particularly if its cold. It takes a few seconds for the car to build pressure. The sound they make isnt great, but its not an issue. People were complaining about it so Audi created a TSB to notify their customers that everything is OK. Its normal. Don't worry about the chicken littles saying that S4 chain guides fail at ~100K. There is no basis for that. It's not a service item. Most cars have plastic guides.


Proper maintenance and owner history is the key. Make sure that the owner took care of the car. Get the car scanned for codes and make sure it has receipts. The V8 S4 is a great car. It's not an exceptionally fast car, but sounds great, rides great and handles relatively well for its weight.

Just be prepared for crap gas mileage and that, like any other premium German car, parts are not cheap if you need them.

 

Thank you for the clarification. I had remembered hearing about it (vaugely) and it was in reference to the RS4. Good to know its not a concern for S4s.

Quote:

Plastic Chain Guides:

I agree with this to some degree...most people do complain and forget to praise on forums, but Audi's do seem to have substantially more maintenance issues than their other German counterparts.

Is there a sound associated when the guides are about to fail? I was familiar with the clacking at start up, but didn't know if there were a tell-tale sign of imminent failure as the miles increase.

Good advice and thanks. Any car would definitely have a PPI performed and I want someone who was religious with their maintenance (preferably at a dealer where it was recorded). The only car I have been truly interested in up until now had zero maintenance records and only a recent brake job...I immediately forgot about that car.

The mileage I would be okay with. It would cost me an additional $500/year in gas given my typical commute and driving habits over my WRX. Worth it so long as I am really enjoying the car.

Any additional feedback is very much appreciated!

 

I'm in the same boat not for a Avant but a regular S4. I glad I read the comment about the auto transmission. ..
I guess I will just keep looking for the 6 speed.

 

You are in a significantly better boat as the "avant" qualifier really cuts down on the number of cars out there. Ebay has had a max of (2) B6 S4 Avants over the past few weeks...AutoTrader has between 10-15...most of which are automatic.

That said, the more I plug cars into KBB and NADA, it is amazing how much slight mileage differences affect value/pricing. Even going from 60k miles to 72k miles has a drastic affect on pricing ($4k-6k cheaper on an '05). If nothing else, it indicates the common understanding of higher mileage Audi issues.

Good luck on your search!

 

Like people above stated... you should be safe with 80k on the clock, as long as the car has been meticulously maintained... and not just ragged daily. I've seen these cars with over 130k and no major problems. Yes some of the owners run in to timing chain tensioner rattles. However majority of these cars are very solid and reliable.

 

Is the timing chain a necessary replacement item at 100k miles or is that just something people try to stick by around the 100k mile mark (I know you just mentioned the guides...but alot of B6s seem to have a new timing chain as well)?

From your sig, how was the switch from the STI to the S4? My switch would be different in that mine is "just" a WRX wagon with a tune, exhaust, suspension work, etc. It might make 230whp or so and while it handles well, it tends to push in turns as I have become accustomed to in an AWD vehicle.

Can you give me your STI to S4 thoughts in terms of performance and just ownership in general?

Thanks.

 

Love my s4.... Nothing feels as safe to me ...bulletproof. I may actually be selling it though...wife feels I don't need to sports cars...;(.

 

often higher mileage vehicles, if well maintained, are a much better buy than 'mid' mileage vehicles. Usually around 80k on Audi's you'll run into control arm issues, need timing belt replaced (not on 4.2 though). I'd take a lower priced 80k mile car with good maintenance records and recent complete service and/or major components already changed out over a 60k mile that will need all that done soon, and cost more up front.

 

The consensus on the Internet about V8 S4s is that although the oil change interval is 10k miles, you should really do it every 5k miles, because clean oil is supposed to be a major variable for engine life. These cars carry 9.5 quarts of synthetic oil so some owners might not have done the 5k interval. It's something to look for in the records.

 

My first post here and I have the same car compliment as the OP. I currently own an '05 WRX wagon cobb stg 2, a '98 m3 (stock motor) with BBK and GC c/o and sway bars, etc and I recently purchased an '04 s4 avant w/ miltek dp and miltek CB.
Here's my take on the 3
WRX; I have grown to really like this car. Stage 2 is quicker than the stock avant and m3 0-60 and for mountain roads is super nimble and fun to drive (i have dialed out 99% of the understeer and I really like the way my WRX feels though). The WRX feels cheap and light and noisy. Parts are relatively cheap and the car has been bullet proof for the most part. I had Wilwood BBK on the WRX and it was fantastic. I really wanted to step up to a vf34 but never did for fear of tranny issues and at that point the WRX becomes $$ to fix.
E36 m3 is not quite as quick as the WRX or the s4 but feels much more connected to the road and is by far the easiest of the three to drive spiritedly. Ive never taken any of these to the track but im sure the m3 would be best on the track, but on real mountain roads, the awd cars seem better, even if they are not as accurate. This is also by far the least expensive of these to maintain (actually super cheap to own) and with the addition of a turbo would flat destroy either the wrx or s4 on power.
I just bought the avant to replace the WRX. Its a far nicer car to drive, has more storage space the v8 is also way easier and fun to drive at speed (no turbo lag, lots 'o torque) and the car obviously has that euro feel to it (great steering, good seats, great brakes). My car was meticulously maintained and during its life the Avant has needed (coils, idlers, window regulator, vc gaskets, front wheel bearings, and slew of other stuff...all replaced before I bought it) and now it needs a clutch and new cats....regular replacement parts are somewhat spendy, but higher-end parts are silly expensive (my wife has a cayenne turbo and Porsche parts are way over priced too). So, to sumerize if the s4 is worth it, my answer is yes. With a few mods guys are running very low 13 sec 1/4 mile (not that im a drag racer, but this just tells you the potential), the car is a pleasure to drive, I dont feel like a teenager driving it, and buying used you should not loose too much in depreciation. Maintenance costs are higher, but I believe that after the main stuff gets sorted, the car should live a long healthy life.

 

Thats some awesome feedback and the similarity between our car collections is wild.

My M3 has every bolt-on imaginable (Coilovers, Sways, Brembo BBK) and I also had Chuck Stickley build an OBD1 3.2 for me nearly 5 years ago. There is no question that my M3 would demolish my WRX.

Also, you mention adding a turbo to the M3, which I did a few years back to a sedan I owned in conjunction with my '95 Coupe mentioned above. The car also had a full suspension, fully built/forged 3.2 motor, GT35R turbo which put down 535whp and 545 wtq @ 22psi. The car was truly the best of both worlds as it handled beautifully and would trounce anything I came across. The area under the curve was incredible (full boost and peak torque from 4k rpms through redline). The only downside is that it had something of a 930 feel in the mountains where if you hit boost at just the wrong time, the car was very tail-happy. This was easily remedied through entry/exit RPM and power application. Despite it being an absolutely awesome car, the 3.2 is not an easy motor to apply heavy boost to without issue. Even when using ARP headstuds, anything over and above 18psi is risking pressuring the coolant system as the head lifts. My car ran 22psi (on pump 93) very well for 8 months but I was always concerned about lifting the head and even backed the boost down to 18psi for most daily duties (~500whp). Technology has gotten better in the past 2 years since I sold it (better o-ringing techniques and headgasket technology), but its still a car that can become a handful with a good deal of boost. Throwing 8psi (340whp) is another story and provides an awesome platform with tons of reliability...but who is happy with just 8psi

I definitely have a difference of opinion with regard to the better handling car in the mountains. My WRX with Cusco swaybars and eibach springs has what feels to be like a wild amount of understeer. This is something I have found true of most all AWD cars, including my father's 996TT. My M3 has zero which is a good thing, until you over-exceed the limits of the tires.

Funny that you mention not feeling like a teenager in the S4, as despite being young, I hate when people think that because I am driving a WRX, I want to race them in school zones, etc. (honest to god, a PT cruiser tried to race my a few months back)

Thanks again for your feedback. I am still holding out for Dolphin Gray, though am warming to the idea of the standard silver.