The B9 uses the EA839 turbo V6, whose family had an early rocker-arm concern (the same issue discussed on the RS5 B9). The smart pre-purchase questions are about valvetrain work and any ticking/knocking/rough cold idle, plus routine PCV, water pump, and thermostat history. …
The 3.0 turbo V6 (EA839) — ask about the rocker arms
Audi S5 (B9) · mechanical