Audi S4
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.
354 hp company car — objectively fast, subjectively empty
Fast, quiet, completely sterile. Active Sound from the speakers instead of real V6 noise, steering that informs but never communicates, AWD that delivers traction without ever being noticed. Objectively better than the B7 at everything except making you feel something. The right car for a fast commute — the wrong car for a driving experience.
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 7
Defective coolant valves cause coolant loss that can silently lead to overheating. Temperature sensors and thermostat housing are a weak point from 60,000–100,000 km.
The rubber bushings in the upper control arms wear prematurely, in some cases from as early as 60,000–80,000 km. The issue is said to have been fixed only with the 2019 facelift.
Certain 19-inch tyre combinations on the B9 lead to premature wear on the inner flanks. The cause is a suspension setup not optimally tuned for larger wheels. Regular wheel alignment recommended.
The S tronic dual-clutch gearbox judders when pulling away and at low speeds. The mechatronics unit can become defective.
Water pump and thermostat housing typically fail between 60,000 and 170,000 km. A well-known weak point on the 2.0 TFSI and 2.0 TDI.
The S tronic dual-clutch gearbox exhibits a known juddering in D and R at idle that Audi classes as within the state of the art. Diesel variants may additionally creep.
The MMI infotainment system frequently exhibits Bluetooth connectivity problems in facelift models: choppy music playback, missed ringtones. Software updates do not always provide a permanent fix.
Reports & Tests
314 owner complaints filed with NHTSA (2015–2026). Most reported: Electrical (121), Other (92), Engine (49).