Audi 55 TFSI e
EA888 evo4 plug-in hybrid with 195 kW combustion engine and 105 kW electric motor. Further development of the DLGA with slightly higher engine output and a larger 17.9 kWh battery.
Touring comfort yes, driving fun no — as intended
Up to 85 km on electricity alone under ideal conditions. The hybrid system is well integrated, the transition between e-motor and combustion engine barely perceptible. Not a driver's car, but an excellent work tool.
Engine Weaknesses 9
The high-voltage battery in DRYA vehicles is affected by the Samsung SDI cell module defect. Overheating can occur during charging. KBA recall 93AD, approximately 17,000 vehicles in Germany.
Symptoms: High-voltage battery warning; charging stops without apparent reason; Audi recommends avoiding external charging until software update.
The facelift variant's hybrid gearbox shares its fundamental design with the predecessor. Gearbox failures on Q5 and A7 55 TFSI e have been documented from around 20,000–80,000 km.
Symptoms: Juddering on pull-away; shifting problems between gears; gearbox emergency programme active; fault message in instrument cluster.
Despite improvements over the evo3, the EA888 evo4 timing chain can show stretch from around 110,000–140,000 km with poor oil maintenance. Rattling on cold start is the first warning.
Symptoms: Metallic rattling from engine bay on cold start; fault codes P0016/P0017; power fluctuations.
Known weak point of the TFSI e charging infrastructure: charging port microswitch fails from moisture, the on-board charger may be defective or deliver half its rated power.
Symptoms: Warning 'charging system locking fault'; charging fails; vehicle does not charge at public stations; charging time doubles.
The larger 17.9-kWh battery is subject to the same ageing mechanisms. Within the 8-year warranty, 70% capacity is defined as non-defective.
Symptoms: Electric range below 35 km instead of the original 45+ km; below 20 km in winter.
In PHEV mode with empty high-voltage battery on pure electric city driving, the 12V battery can discharge. Inadequately protected in early software versions.
Symptoms: Sudden 'battery weak' warning after pure electric driving; vehicle fails to start.
The longitudinally mounted EA888 water pump is prone to leaking. Coolant loss and in severe cases coolant ingestion into the vacuum system can cause secondary damage.
Symptoms: Dropping coolant level without external leak; overheating warning; fault code P0299.
Despite optimisations the direct-injection principle remains. Without port injection, deposits accumulate on intake valves — aggravated by frequent EV-mode operation with rare combustion engine runs.
Symptoms: Cold-start judder and rough idle; power loss below 2,000 rpm; increased fuel consumption in hybrid mode.
With predominantly regenerative braking, the rear brake discs get little mechanical cleaning. Road salt in winter accelerates corrosion considerably — TÜV rejection possible.
Symptoms: Visible rust on brake discs; grinding noise on first brake application; inspection rejection.
Vehicle Weaknesses 5
Contamination of the bonding surface during manufacture can cause the rear panoramic roof module to detach. Affects A6 models produced in 2018.
Stress corrosion cracking can cause excessive play between the control arm and wheel carrier on the A6 C8 (MY 2019–2021), impairing driving stability. Recall by KBA (action 42L1), free repair at dealer.
High-voltage battery cell modules on A6, A7, Q5 PHEV models can overheat during charging (KBA 15722R / code 93AD). 53,449 vehicles worldwide, 17,012 in Germany affected (production period 08/2019–08/2024). Software update takes approx. 60 minutes.
The MMI infotainment system stands out for frozen displays, unexpected reboots and Apple CarPlay/Android Auto failures. Software updates only partially resolve the problem.
On some A6 C8s, water enters through a leaking wheel arch liner, causing musty smells and moisture in the footwell or boot.