Audi S6
EA897 evo (3rd generation 3.0 TDI), fitted from 2016 in A4 B9, A6 C8 and Q5 FY. The fully electronically controlled oil pump deliberately reduces pressure at idle — a design feature that can become a liability with age. Camshaft failures and low oil pressure are known major damage patterns.
V6 replaces V8 — quick, efficient, nobody asked for it
They killed the V8 and replaced it with a V6 and a 48V system. Quick? Yes. Efficient? Yes. Nobody asked for this. The C7 with its twin-turbo V8 is climbing in value while C8s sit at dealers. Three of four C8 buyers on Audizine traded for an S8 — the only way left to get a V8 in the S-range.
Engine Weaknesses 5
The ECU-controlled oil pump reduces pressure at idle to approx. 1.0–1.4 bar. At high motorway oil temperatures with bearing wear, this pressure is insufficient — con-rod bearings seize from 150,000 km.
Symptoms: Oil pressure warning at idle or on country roads, knocking noises, in severe cases engine failure
All 272-hp variants built before January 2017 contained faulty camshafts. Tooth flank noise and fractures are possible; Audi acknowledges the problem, goodwill depends on mileage.
Symptoms: Clattering or ticking from camshafts even after brief warm-up, rough running, in severe cases sudden engine stall
The EA897 uses four timing chains — one per cylinder bank, one connecting chain and one for the oil pump. All chains, tensioners and guides must be renewed together.
Symptoms: Rattling on cold start, metallic knock on throttle, engine light with camshaft faults
Injector failures with oil dilution from fuel ingress. Less common on EA897 evo than predecessors, but costly to repair: replacing multiple injectors can cost €4,000.
Symptoms: Rough engine, rising oil level (fuel ingress), heavy soot production, increased consumption
The 3.0 TDI in the SQ5/S4 B9 needs sufficiently long runs for DPF regeneration. Predominantly short-trip use accumulates ash in the filter. Above 45 g load, ceramic melting is at risk.
Symptoms: Engine warning light 'particulate filter system fault', noticeable power reduction (limp mode), increased fuel consumption. DPF regeneration runs more frequently and for longer.
Vehicle Weaknesses 5
On vehicles from model year 2018 the panoramic roof can detach due to adhesive bond failure. Audi issued a recall; confirm completion before purchase.
The 48V belt-driven starter-generator (BSG) is a known weak point of the C8. When it fails the entire 48V electrical system goes offline. Audi granted an extended warranty of 7 years on the component.
On some C8 models moisture enters through a leaking wheel arch and causes a musty smell inside the vehicle as well as possible corrosion on electrical components.
On the S6 C8 the adaptive cruise control (ACC) and MMI infotainment system drop out sporadically. The automatic emergency brake triggers too early. Primarily affects 2018–2021 models.
The S6 C8 with 450 hp and a 2,000 kg kerb weight places heavy demands on the braking system. Spirited use leads to frequent brake disc replacement, especially on the front axle.