Audi RS5
The 2.9 TFSI V6 BiTurbo was developed in collaboration with Porsche — related to the engine in the Boxster/Cayman GTS and Macan Turbo. Twin-scroll turbos in the Hot-V, 450 PS and 600 Nm from 1,750 rpm. Central wear issue: rocker arm bearings in the cylinder head. Early batches (before GP1 production code, approximately up to mid-2019) had rocker arms with too-small bearing rollers — risk of fracture, rollers falling into the sump. Improved from GP1 onwards. When buying a B9 RS4/RS5 built before mid-2019: check the production code. Preventive retrofit is possible — part costs £16, but engine removal required.
RS5 Coupé — same BiTurbo V6, better proportions
Same 450 hp twin-turbo as the RS4 B9, but more cohesive in a coupé. The lower roofline suits the GT character better than the wagon. Missing the B8 RS5 V8 sound? Yes. Still a seriously fast GT coupé? Also yes.
Engine Weaknesses 5
In the 2.9 TFSI BiTurbo (DECA), rocker arm bearing rollers can fall out of the cylinder head and end up in the oil pan. Early production years (up to approx. 2019) are especially affected. A revised design with thicker bearing rollers was introduced. No official recall, but serious consequences are possible.
Symptoms: Knocking or rattling noises from the cylinder head, metal particles in the engine oil, sudden power loss, engine fault codes
As a pure direct injector without port injection, the EA888 DECA builds pronounced soot deposits on the intake valves. Crankcase ventilation oil mist and EGR gases thermally bond to the valve heads. Cleaning from 40,000–60,000 km onwards is recommended.
Symptoms: Creeping power loss, stumbling under partial load, rougher idle, increased fuel consumption especially in city traffic
The 2.9 TFSI DECA shows elevated oil consumption with spirited driving due to high thermal loads and boost pressures. Coked piston rings worsen the problem. Regular oil level checks between service intervals are essential on the RS4/RS5 B9.
Symptoms: Dropping oil level between oil changes, occasional blue smoke under hard acceleration, light oil smell
Both turbochargers of the 2.9 TFSI DECA can lose shaft seals at high mileage or with aggressive use. Oil consumption rises, oil mist enters the intake. Since both turbos are on the inner engine side, removal is very labour-intensive.
Symptoms: Increasing oil consumption, light blue smoke, oil traces in the intercooler, whistling under load
The 2.9 TFSI DECA uses a timing chain system where tensioners wear and can cause rattling on cold start. High power output and spirited use increase the load on the timing drive. Early tensioner replacement prevents chain elongation.
Symptoms: Rattling on cold start that subsides at operating temperature, camshaft fault code, MIL with timing chain fault
Vehicle Weaknesses 15
Oxidation on the occupant detection system (PODS) connector cable causes a false diagnosis that deactivates the passenger airbag even when the seat is occupied. Approximately 243,000 vehicles affected.
Stress corrosion on the rear axle attachment nut can cause play between the control arm and wheel carrier. A subsequent action (42L5) omitted a wheel alignment check, leading to uneven tyre wear on one side.
2019–2021 model years can develop stress corrosion cracking in the trailing arms, leading to increased play and unstable handling. Inner flank tyre wear is a typical symptom.
Display goes dark while driving; only the speedometer and rev counter remain visible. HUD fails simultaneously, steering wheel controls become unresponsive. A software update usually resolves the issue; unit replacement is rarely needed.
At higher mileages, control arm bushings and joints on the front axle wear out. The sport suspension setup promotes premature wear of the rubber bushings, especially with frequent motorway use.
The S-tronic gearbox occasionally shows harsh shift behaviour. Neglected gearbox oil changes (interval 50,000–60,000 km) worsen the judder and delayed shifts. Hard engagement when changing up under full load.
The optional sport differential requires an oil change every 30,000 km. This is not listed in the service schedule by many Audi dealers, leading to premature wear.
Navigation favourites delete themselves, the sat nav reinitialises while driving. Bluetooth connections are forgotten, wireless CarPlay works sporadically.
Standard sport brake discs and pads wear considerably faster than on the A5 under spirited driving. Brake discs warp under heavy thermal load. The front axle is more affected.
Early F5 models built until late 2017 were delivered with non-stainless-steel exhaust systems. From spring 2018 Audi fitted stainless steel as standard. Iron rust on centre and rear silencers is typical.
The starter battery shows low-voltage warnings after only a few years. The many control units in the F5 place a constant load on the electrical system. Cold-start problems in winter are an early warning sign.
Early model years up to end of 2017 have faulty 360-degree camera systems. The camera image freezes or the camera stops responding. Software update or camera module replacement required.
Vehicles up to spring 2018 were delivered with a steel exhaust that is prone to corrosion. From spring 2018 Audi switched to stainless steel. Affects early F5 model years primarily.
The headlight levelling system on the RS5 F5 shows persistent malfunctions across all model years that were never fully resolved. Driving with incorrectly aimed headlights can dazzle oncoming traffic.
Trim panels on the A, B and C pillars and the dashboard produce creaking noises at temperatures around 20–25°C. On the Cabriolet this is amplified by body flex.