Yes, owned both a B5 S4 and have just recently given away an A6 2.7T which is basically the same under the bonnet.
Things to watch out for are;
Noisy turbos (KO3's don't often last beyond 100k and are usually replaced with KO4's from the RS4 which are much more reliable and can run more power)
Boost leaks
Faulty diverter valves
Faulty N75
Water temp should always be on 90deg once warm, any fluctuation can hint at thermostat failing
Check it's had cambelt / water pump / thermostat done
Noisy wheel bearings
Electrics - check all windows work
TBB can split - throttle body boot
MAF Failure is quite common
Great cars, really enjoyed both of mine. Many have now been remapped and may have had pre-cats gutted, air filter replaced, diverter valves upgraded, Throttle Body Boot TBB replaced and N75 replaced. Other common upgrades include turbo and intercooler upgrade.
Jules.
Last edited by Cyclone; 05/10/2012 02:10.
