Audi RS5
Facelift version of the 2.9 TFSI V6 BiTurbo with OPF and 48V mild hybrid — 450 PS like the DECA, but with particulate filter and BSG starter-generator. The OPF noticeably mutes the V6 sound; the mild hybrid delivers brief boost pulses during launch. The rocker arm bearing issues of the DECA also affect the DNXB — same design, same wear pattern on the exhaust camshaft rocker arm bearing. The water pump is a known weak point as with the DECA. Compared to the DECA: less emotional, but slightly more economical in everyday use through regeneration and coasting.
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 6
Design flaw: water pump leaks internally and draws coolant into the vacuum system. Can cause severe engine damage if not stopped immediately. Improved 6-bolt version available as replacement.
Symptoms: Coolant loss in expansion tank, fault codes P0299, drive interruption message, coolant deposits on engine block bank 1
Small bearing rollers on the rocker arms detach on early units (GP0-P code) and fall into the sump. Caught early, replacement costs a few thousand euros; undetected, total engine failure.
Symptoms: Ticking or knocking on cold start and at idle, engine warning light, metallic noise from cylinder head area
Two turbos in the V6 are exposed to severe heat. Insufficient warm-up and immediate shutdown after full load substantially accelerates bearing wear.
Symptoms: Whistling from turbo area, smoke from engine bay, power drop, increased oil consumption, blue smoke
The 2.9 TFSI V6 BiTurbo uses a cooled indirect charge-air system. Oil supply to both turbos is critical on cold start. Insufficient cool-down after hard use can damage turbo bearings.
Symptoms: Whirring after engine shutdown, smoke from exhaust on cold start after hard use
S-Tronic (PDK) on the RS4/RS5 B9 shows accelerated clutch wear with frequent track/sport use and launch control. Stop-and-go city driving makes it worse.
Symptoms: Juddering on pull-away, dual-clutch noises, gearbox control faults
Turbo direct-injection without port spray. Deposits build on intake valves with frequent short trips or skipped cleaning intervals.
Symptoms: Power loss under partial throttle, rough idle, increased fuel consumption, sluggish throttle response
Vehicle Weaknesses 16
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.
The third brake light seal becomes porous and allows water into the tailgate. Water can damage expensive antenna modules. Affects the Sportback.
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.