Audi S4 (B6/B7)

298 sales analyzed · 5 topics from real Bring a Trailer & Cars & Bids comments.

“I have a drinking game, every time a B6 or B7 S4 comes onto bringatrailer, take a shot when someone asks about the timing chain guides.”Slant4 · Mar 16, 2020

• Timing-chain guides are THE defining concernmechanical
  The 4.2 V8's plastic timing-chain guides/tensioners wear and are the single most-discussed B6/B7 S4 topic — to the point of running jokes. The chains are at the rear of the engine, so addressing them is an engine-out job. …
• Doing the chains right: ~$7k, year matters, metal guides + water pumpbuying-advice
  The chain kit is cheap; the labor is the cost — budget ~$7k, or $11-12k if you also need cats/emissions work. Early 2005 cars had the worst guides; Audi revised them for 2006 and 2007. …
• Not every car needs chains — risk varies by carmechanical
  Despite the reputation, plenty of B6/B7 S4s run well past 100k on original guides — longtime owners report cars (including Tiptronics) that never needed the job. The practical approach is to verify with a cold-start video for chain rattle and check service history rather than assume failure. …
• No carbon worry — the S4 4.2 is not direct-injected (unlike the RS4)mechanical
  A key distinction owners draw: the B6/B7 S4's 'BHF' 4.2 is port-injected, so it does NOT suffer the intake-valve carbon buildup that the RS4's direct-injected 'BNS' 4.2 needs walnut-blasting for. In short — the RS4 has carbon (no chain issue); the S4 has the chain issue (no carbon). …
• A characterful V8 sleeper — manual Avant is the unicornvalue-and-market
  The only V8 S4 is loved for its naturally-aspirated soundtrack and Q-car looks — the ultimate sleeper, especially as a 6-speed manual Avant (the 'longroof'), which commands an 'Avant tax.' Values reward clean, sorted cars with the chain service done; chain-needy cars trade at a discount. …