SloopJohnB@mac.com

Not least is the varnished fuel system, probably seized fuel pump, seized pistons, etc.
You'll need to pull the plugs and squirt in marvel mystery oil or something similar and let it sit for a week before even trying to move the pistons. I would yank the cam covers and inspect the valve train. Remove and clean out the critter nests in the intake/air filter box.

There's a great article in Roundel this month regarding resurrecting an engine/car that was left sitting for 10 years. 5 is a lot shorter, but unless the engine was properly prepared/fogged/sealed and the fuel system prepped (five years ago they still had EtOH in fuel so you can bet the tank is slagged. Anything rubber is suspect, the coolant is now five years older and it was probably suspect when you laid the car up and is certainly due to be changed now.

Go through the entire engine BEFORE you try to even turn it over and do not use the starter!!!!

Good luck.

Ellis Rogers

Just passed 200K in my 1998 A6 2.8 the other day! The thing still runs like a top!

half fast

to the Duke
Perhaps I was a bit harsh with my review of my wifes A6. You are correct that all auto manufacturers have their lemons. I have been very fortunate to have only received the one Audi produced. I owned an '85 VW Jetta Diesel that gave me 250k miles before I handed it down to my son for his first car. He was 1 year old when I purchased it new. I had no mechanical issues with that car for its entire life. The Mercedes I have owned (and still do) are the '90 300E 3.0 liter, a '97 E320, and a '98 E320 4matic wagon. Our success with the brand prompted my son to recently purchase an '08 E350. I actually have owned many other vehicles and brands over the last 45 years and can honestly say the Audi has been the most disappointing purchase that I have ever made. You are also correct that I am to blame for not doing more research prior to the purchase.

Prospeeder

This is not always the case but can be. Iv had plenty of good luck with finding cars that have been sitting years and years and with minimal work they run and are good cars again. 5 years is not long enough for pistons to seize tho.

amaranth999

Further to this thread, my 2.8 just reached 380K. Just had the timing belt changed and hope for another 200K. want to see if can reach the 1M mark.

jcman

You must live in a very mild climate no salt on road or in the air.

kelisko

1,000,000 Km here with an A4 B6. That's about 621,000 miles.

huskyz

"Only" 155k miles on 98 2.8 A4 5 speed. It runs great, but despite efforts to solve, leaks require regular oil checks. Belt/pump changed 2nd time at 135k, plugs twice I think. Nothing else of note. Car would run a lot longer but now needs control arms and some other stuff and we (especially wife) losing interest, time, and need for another AWD in winter where this car is amazing.

Our new S4 and other cars are getting most miles and (more important) the garage bays now, so 98 now sits outside, and is unhappy doing it. It's too bad. We bought it new and loved it...a great car...if maintained. All oil changes at < 5k miles (Castrol)...my Euro Indie garage said they hadn't seen a cleaner old/mileage Audi motor. (But it IS an Audi, and will always require something).

To the OP my guess is the engine would easily outlive us (at our age..) if we kept and cared for it

Bravomalaga

Hello,
Sorry to bother you. I write you because i am thinking in buying a second hand audi s6.
It is a 120k miles one with timing belt changed and rotors also.
As a owner what do you think?
Is the engine strong enough?
Could you please tell me your experience??
Additionally, do you know if is easy to access the different parts in order to do maintance on my own??

SloopJohnB@mac.com

I put a rebuilt trans (from Audi) in at $107K and I babied the thing from 64K on when I bought mine used in 2008; trans fluid and filter changed before I brought it home. The engine is pretty strong and reliable and you can do most of the maintenance on your own. Unless you've changed a timing belt on an interference engine before, this is probably not the first one to start on although depending on what you pay for the car you might blanch at $2K TB service (includes tensioners, water pump, idlers, serpentine belt and tensioner, etc.). The engine is strong enough to do 155+ (speed limiter but that can be removed through ECU reprogram or reflash...I don't recommend it) and it's very nice. The intake manifold flaps and the controller/vacuum motors are an issue; they WILL carbon/sludge up and freeze. A new intake manifold complete with vacuum motors is about $1600 these days. I've put on at least one although it was covered under the extended warranty I bought from Audi.
The catalytic converter(s) were covered by Audi for 10yrs/100K miles on a free extended warranty by Audi (apparently there were issues and they settled with EPA); in my case the cats were fine (I still have the OEM 02 sensors at 145K+) but the flex pipes rotted/failed.

At 120K mi you're looking at shock replacement (although I have 145+ on my 02S6) perhaps. Good that it has new rotors and pads, that's around 3-400 if you do it yourself; a lot depends on what pads are used. Some people put extremely low dust pads on and sacrifice stopping/fade power. You don't need gonzo race pads (bad on street anyway, need to warm up) or Hawk HP+ (great pad, relatively easy on rotors, but as dirty or worse than OEM), Hawk HP are sufficient and they're slightly less dusty than OEM.

140K you should consider replacing the voltage regulator (worn brushes) or be prepared to do so sooner or later. The battery is tough to replace; heavy as hell and right up near the windshield, 95AH OEM but you could probably fit a 75AH in there...the clamp adjusts for shorted batteries.

These things are freakin' expensive to repair...a minor fender bender cost my insurance company almost $12K and I was out the car for almost 4 months, including the time it was at the dealer post-collision shop for additional repair ($2K included in the 12K above).

I wouldn't pay more than $8-10K for one with 120K on it. Mainly because of the transmission issue.