Audi A6 C8 (2018-2025): known problems and buying guide

A quiet, roomy executive car with a costly 48 V generator risk on early cars, so check the generator and software history first.

Updated 27 October 2026

All versions

Variant	Running cost per month	Median price	Listings	Fuel	Engine codes	Gearbox	Production years
40 TDI, 204 PS, 7-speed dual-clutch Research	€544	€37,950	262	Diesel	DTP	Automatic (dual-clutch) (7)	2023–2025
40 TDI, 204 PS, 7-speed dual-clutch, all-wheel drive Research	€544	€37,950	262	Diesel	DTP	Automatic (dual-clutch) (7)	2023–2025
45 TFSI, 265 PS, 7-speed dual-clutch Research	€576	€35,840	248	Petrol	DMT	Automatic (dual-clutch) (7)	2023–2025
45 TFSI, 265 PS, 7-speed dual-clutch, all-wheel drive Research	€588	€35,840	248	Petrol	DMT	Automatic (dual-clutch) (7)	2023–2025
S6 TDI, 344 PS, 8-speed automatic, all-wheel drive Research	€719	€47,690	247	Diesel	DMK	Automatic (8)	2023–2025
45 TDI, 245 PS, 7-speed dual-clutch, all-wheel drive Research	€614	€40,880	79	Diesel	DMG	Automatic (dual-clutch) (7)	2023–2025

Years: 2018 to 2025; facelift in 2023. Saloon, Avant and allroad.
Reliability: 3/5. The 48 V belt starter-generator is a costly failure on 2018-2020 cars, and early infotainment is glitchy.
DIY: 1/5. The 48 V system and the software work need an Audi dealer with the ODIS diagnostic tool.
Prefer: a 2021 or later car with a full Audi service history and proof of the generator and software updates.
Avoid: 2018-2020 cars without proof of a generator repair or the latest software.

2.0 TDI EA288 evo (DEZ, DFB, DTP), 2018-2025: 163 and 204 PS. See the EA288 guide.
3.0 TDI V6 (DDV, DMG), 2018-2025: 231 to 286 PS. The 50 TDI can hesitate when pulling away; a software update is the fix.
S6 TDI (DEW, DMK), 2019-2025: 344 to 350 PS. It shares the pull-away hesitation; a software update is the fix.
2.0 TFSI (DKN, DMT), 2018-2025: 245 and 265 PS. See the EA888 guide.
3.0 TFSI V6 (DLZ), 2018-2025: 340 PS. No fault confirmed in the sources read.
Plug-in hybrid 50 and 55 TFSI e (DLG, DRY), 2019-2025: 299 and 367 PS. No fault confirmed in the sources read.
RS6 4.0 TFSI V8 (DJP, DYG), 2019-2025: 600 and 630 PS. No fault confirmed in the sources read.
7-speed S tronic DL382: See the DL382 guide.
8-speed tiptronic: no A6-specific fault confirmed in the sources read.

Issue	Affects	Typical km	Repair cost
48 V belt starter-generator failure	Cars built 2018-2020, several engines	Not stated	1,190-2,300 EUR (ADAC, Germany, year not stated)
MMI and infotainment faults	Early cars, about 2018-2020	Not stated	No confirmed price
Sluggish pull-away on the 3.0 TDI V6	3.0 TDI V6 (DDV, DMG) and S6 (DEW, DMK)	Not stated	No confirmed price

48 V belt starter-generator: on a 2018-2020 car, start it from cold and look for a network warning. This check needs a scanner; a dealer with ODIS should read the generator and 48 V battery faults. Bad: a yellow or red network message, a warm idle stuck near 1,000 rpm, or start-stop switched off.
MMI and screens: test both screens, sat nav, radio, climate and driver-assist systems together. Ask for the software version and the date of the last update. Bad: a screen that freezes, lost favourites, or a warning that cruise control is not available.
3.0 TDI pull-away: drive a 50 TDI or S6 from a stop and at low speed. Bad: a long hesitation before the car moves. Ask whether the engine and gearbox software updates were done.
Recalls: ask an Audi dealer to check open campaigns by VIN, especially the panoramic roof, passenger airbag and rear axle campaigns.

Operational	€210
Workshop	€149
Fixed costs (tax, insurance)	€227
Total per month	€586
New-car depreciation (not included)	€308

ADAC figures for 15,000 km a year over 60 months

Listings on mobile.de priced up to 50,000 EUR, 29 October 2026.

To check a listing's price, open its variant in the table above. Each variant page has a price check.