Audi A6 C8 — Problems & Common Faults
Weaknesses, engine ratings and buying advice
The Audi A6 C8 (2018–2024, internal code 4A) is the digital-era executive sedan — and a car with one defining issue that overshadows everything else: the 48V Belt Starter Generator (BSG). This single component triggered a class action, forced Audi into a 10-year warranty extension, and landed the C8 at dead last in the 2021 What Car reliability survey: 24th out of 24 in its class, scoring 76.3%. By 2025, the C8 had recovered to 14th out of 23 — proving that the early cars were genuinely problematic while later production sorted itself out.
The BSG is a 48V mild-hybrid starter-generator integrated into the accessory belt drive. On early C8 models (2018–2020), it fails with alarming regularity — complete electrical system shutdowns, engine stalls at traffic lights, inability to restart. Audi issued a 10-year warranty extension specifically for the BSG unit. On any used C8, the BSG warranty status is the single most important piece of paperwork. Confirm it exists, confirm it has remaining coverage, and confirm whether the BSG has already been replaced. Without this documentation, budget $1,800–3,500 for replacement.
The engine lineup: 45 TFSI (2.0 turbo, 195 kW) is the adequate entry — EA888 Gen3B with 48V MHEV, sufficient torque, reasonable consumption. No dramatic weaknesses beyond the BSG system. 55 TFSI (3.0 V6 turbo, 250 kW) is the sweet spot — the EA839-derived V6 delivers effortless power, pairs with the ZF 8-speed Tiptronic (more robust than S-tronic), and feels like a natural fit for a 1,800 kg sedan. Water pump monitoring recommended (shared EA839 architecture with the Cayenne 9YA).
50 TDI (3.0 V6 diesel, 210 kW) is the highway-only proposition. Magnificent long-distance cruiser — 800+ km range, 6–7 L/100 km at 130 km/h, 600 Nm of torque. But the DPF (diesel particulate filter) punishes city driving. Short trips under 15 km without highway regeneration cycles lead to DPF clogging, forced regenerations, and eventually DPF replacement ($2,500–4,500). If the service history shows primarily urban driving, walk away from any 50 TDI. The 40 TDI (2.0 diesel, 150 kW) is the sensible diesel — less DPF stress, lower purchase price, adequate for mixed use.
Transmission: The S-tronic DL382 (7-speed dual-clutch) on 45 TFSI/40 TDI carries the same risk as the A4 B9 — Audi declares the oil as "lifetime fill," reality demands changes every 50,000–60,000 km. Mechatronic failure from 60,000 km without oil service. The ZF 8HP Tiptronic on 50/55 TFSI and 50 TDI is fundamentally more robust. When buying used: Tiptronic is the safer transmission.
The S6 C8 runs a 2.9 V6 TDI (257 kW) with electric compressor — the only diesel S6 ever built, a unique proposition. The RS6 Avant C8 with EA825 4.0 V8 biturbo (441 kW) is mechanically robust but carries PHEV battery complexity in the TFSI e variant.
Air suspension (standard on 55 TFSI, optional on others): same architecture as A7/A8 — bladder leaks from 80,000 km, compressor $900–1,500, full corner repair $1,500–3,500. MMI blackouts (both screens go dark, ADAS fails) are common on early production — dealer software update usually resolves it.
Test-drive checklist: BSG warranty documentation — this is non-negotiable. Cold start: does the engine restart cleanly after every stop? Drive in stop-and-go traffic for 10 minutes — any electrical system warnings or restart hesitation = BSG issue. S-tronic: judder on launch below 20 km/h. Air suspension: level after 30-minute standing. Diesel: DPF regeneration history in OBD. OBD full scan mandatory.
2026 market: 45 TFSI 2019 from $28,000–38,000. 50 TDI 2019–2020 from $30,000–42,000. 55 TFSI from $38,000–52,000. S6 TDI from $55,000–72,000. RS6 Avant from $88,000+. Insider pick: 2021+ Avant 50 TDI with highway service history, BSG warranty confirmed — the facelift-era production resolved the worst BSG reliability issues, the diesel V6 is unmatched for long-distance use, and the Avant is the quintessential estate car.
630 PS
RS6 Avant Performance · Benzin
600 hp wide-body icon — Instagram star with real substance
Legendary!265 PS
2.0L TFSI Benzin
6 weaknesses
Good Choice231 PS
3.0L TDI V6 Diesel
6 weaknesses
Stay Away!Body Variants
The Audi A6 C8 is available as Sedan and Avant — choose your body type for specific insurance data:
Generations
Engine Overview
The Audi A6 C8 is available with 15 engine variants — from 136 to 630 hp. 5 variants had engine changes — the model year is crucial.
EA288 evo 2.0 TDI with 120 kW — common rail for the upper mid-size class, twin dosing with two SCR catalysts. Timing belt plus oil-bath belt for oil pump — dual-system risk as all EA288. EGR from 80,000–100,000 km. DPF on short trips. Cam oil seal leak → oil on dry belt. Belt at 150,000 km recommended. HP pump failure contaminates system. AdBlue valves clog (tank + ECU ~€1,700). More stable than EA189. Economical on long distance. Oil VW 507.00/509.00, every 15,000–20,000 km.
- !! EGR Cooler Crack and Coolant Loss from 100,000 km
Cracks in the EA288 EGR cooler allow coolant to enter the exhaust tract. Long-term, gradual coolant loss occurs; white smoke and engine protection warnings follow. Untreated, cylinder head damage is possible. Problem occurs from around 100,000 km.
Symptoms: Coolant loss with no visible external leak, white smoke from exhaust, engine overheating warning, coolant smell - !! Wet Timing Belt Premature Wear from 150,000 km
The EA288 uses a wet timing belt running in oil instead of a chain. With incorrect oil change intervals or incorrect oil type, the belt material degrades prematurely. Oil traces on the belt from a leaking camshaft seal significantly shorten service life.
Symptoms: Whistling noises at idle, rubber fibres in the oil, irregular power delivery, engine misfires - !! Turbocharger Secondary Damage from DPF/EGR from 160,000 km
On the EA288 2.0 TDI, the turbocharger frequently suffers as a consequence of upstream defects: DPF back-pressure or oil contamination from timing belt debris can damage turbo bearings. Independent primary turbo failures are rarer than on predecessor engines.
Symptoms: Whistling or rattling noise from the turbo, oil mist in intake area, power loss, fault code P0299
+ 2 more engine weaknesses + vehicle weaknesses
Common-rail diesel from the further developed engine generation. The timing drive combines a dry belt for the camshafts with a separate belt running in an oil bath that drives only the oil pump; the manufacturer classifies it as a lifetime part, but workshops replace it proactively well before that point since engine oil gradually makes the rubber brittle. The EGR cooler can develop cracks and leak coolant into the intake tract unnoticed — the giveaway is a slow coolant loss with no visible leak anywhere in the engine bay, documented in some cases from comparatively low mileage. Mostly short-trip driving speeds up particulate filter soot loading.
- !! EGR cooler leak and coolant loss from 90,000 km
The EA288 Evo derivative DTNA shares the EGR cooler leak susceptibility common across the entire EA288 engine family. Cracks in the cooler allow coolant into the exhaust tract. Fault code P0401, coolant loss without visible external leak is characteristic.
Symptoms: Coolant loss without visible leak, white smoke from exhaust, dropping coolant level, overheating warning - !! Wet timing belt in oil bath — wear from 150,000 km
The EA288 Evo DTNA, like its predecessors, uses a wet-running timing belt in an oil bath. With missed or extended oil-change intervals and incorrect oil grades, belt material degrades prematurely. No officially set replacement interval from Audi/VW increases the risk.
Symptoms: Whistling, rubber fibres in engine oil, irregular firing order, engine stutter, ECU faults - !! Oil consumption EA288 Evo piston rings from 60,000 km
The EA288 Evo with aluminium block sometimes shows higher oil consumption than the standard EA288. Some 200-hp Evo engines need around 1 litre per 5,000 km. Low piston-ring tension for friction reduction contributes. Early diagnosis is important.
Symptoms: Dropping oil level between changes, light blue smoke under load, oil smell from exhaust, elevated consumption from the outset
+ 1 more engine weaknesses + vehicle weaknesses
The smaller-output tune of the diesel V6 with 48-volt assistance is likewise affected by the sluggish throttle response below roughly 2000 to 2500 rpm documented for this engine family. The camshaft material defect that surfaced in isolated cases years into production on closely related units of the same generation, with knocking running noise, applies in principle to this tune as well, even though manufacturing quality had already improved noticeably compared with the family's early batches.
- !! Camshaft fracture — 272 hp from 90,000 km
The CZVC 3.0 TDI 272 hp (SQ5, A6, A7) is more severely affected by the camshaft material defect than the 218 hp variant. Audi TPI 2043172 lists CRT-type codes with high unit counts. Affected engines serial numbers 000001–175973. Fracture directly causes engine damage.
Symptoms: Knocking, abnormal noises on cold or warm start, rattling from the valvetrain, sudden power loss - !! Timing chain elongation — V6 TDI 272 hp from 140,000 km
Timing chain elongation on the CZVC V6 occurs particularly when oil maintenance is neglected. The four-chain-plus-belt system for the high-pressure pump requires regular oil changes. Repair costs can exceed €3,000 as 15–20 labour hours are needed.
Symptoms: Rattling on start, camshaft fault codes in ECU, rough running, valve timing alarm - !! High-pressure pump failure — system contamination from 150,000 km
On the 3.0 TDI CZVC a defective high-pressure pump can introduce metal debris into the entire fuel system and damage the injectors. Repair includes pump, rail, high-pressure lines, and all injectors. Audi goodwill was granted in some cases but is not guaranteed.
Symptoms: Starting problems, metallic noises, fuel pressure fault codes, rough running, severe power loss
+ 3 more engine weaknesses + vehicle weaknesses
This early tune of the diesel V6 with 48-volt assistance was among the first units of this evo generation and displayed the sluggish throttle response below roughly 2000 to 2500 rpm documented for this output tier particularly clearly. The camshaft material defect known from the preceding production stage was largely considered resolved by this point, though isolated cases of closely related units from this generation still showed knocking camshaft noise years into production, leading to replacement under warranty.
- !! Timing chain rattles on cold start from 120,000 km
Hydraulic chain tensioners lose oil pressure on cold engine. At start-up the chain rattles loudly for 1–3 seconds. Advanced wear risks chain jump and engine failure.
Symptoms: Loud rattling or clattering directly after cold start, subsiding after a few seconds. With greater wear, rattle persists when warm. - !! Camshaft fracture — material defect from 100,000 km
On 272-hp variants (built up to Jan 2017) camshafts broke due to material defects. On failure, metal fragments can destroy the engine. Audi replaced camshafts as a goodwill gesture.
Symptoms: Clicking or rattling from the valve train, rough engine, engine oil contaminated with metal particles. - !! AdBlue system: pump and injector failure from 80,000 km
AdBlue pump, heating element or injector fails, especially after frost periods. Engine remains unaffected, but the vehicle will not start after several cycles.
Symptoms: AdBlue system fault warning on display, SCR fault codes, restricted drive readiness once warning counter expires.
+ 2 more engine weaknesses + vehicle weaknesses
This late evo tune of the diesel V6 with 48-volt assistance meets the strictest Euro 6d emissions stage. From a certain control-unit revision introduced in summer 2020, the flow-controlled oil pump deliberately lowers oil pressure at low engine speed and warm idle, on affected units down to roughly one bar; left unaddressed this promotes accelerated wear on the crankshaft and connecting-rod bearings, and a software intervention can restore pressure. Like the rest of the engine family, the turbocharger only builds noticeable boost above roughly 2000 to 2500 rpm, which shows up as sluggish throttle response at low revs.
- !! Timing chain rattles on cold start from 120,000 km
Hydraulic chain tensioners lose oil pressure on cold engine. At start-up the chain rattles loudly for 1–3 seconds. Advanced wear risks chain jump and engine failure.
Symptoms: Loud rattling or clattering directly after cold start, subsiding after a few seconds. With greater wear, rattle persists when warm. - !! Camshaft fracture — material defect from 100,000 km
On 272-hp variants (built up to Jan 2017) camshafts broke due to material defects. On failure, metal fragments can destroy the engine. Audi replaced camshafts as a goodwill gesture.
Symptoms: Clicking or rattling from the valve train, rough engine, engine oil contaminated with metal particles. - !! AdBlue system: pump and injector failure from 80,000 km
AdBlue pump, heating element or injector fails, especially after frost periods. Engine remains unaffected, but the vehicle will not start after several cycles.
Symptoms: AdBlue system fault warning on display, SCR fault codes, restricted drive readiness once warning counter expires.
+ 2 more engine weaknesses + vehicle weaknesses
EA288 evo 2.0 TDI with 48V mild hybrid (100 kW/136 PS). Mechanically identical to the 150 PS version DETA, software-limited. Belt starter-generator (BSG) is the critical weak point of the mild hybrid system — known recall (KBA 9831 / Audi action 27H2) for fire risk from moisture. Cam belt in oil bath (wet timing chain) requires scheduled replacement around 210,000 km.
- !! Recall: Belt Starter-Generator Fire Risk (KBA 9831)
Moisture can penetrate the 48V belt starter-generator and form short-circuit bridges, leading to overheating and vehicle fire. Audi action 27H2, approx. 530,000 vehicles worldwide affected (2017–2020). Free replacement of the RSG at the workshop.
- !! 48V Belt Starter-Generator Failure (Battery Deep-Discharge) from 60,000 km
The 48V belt starter-generator (BSG/RSG) can fail electrically and drive the lithium-ion battery into protection shutdown. Result: complete vehicle standstill with a cascade of warnings. Repair costs 1,500–2,300 EUR; a 7-year warranty extension was introduced.
Symptoms: Yellow battery warning, then red warnings in sequence; possible loss of power steering and brake servo; vehicle stops. - !! Wet Timing Belt — Scheduled Wear Item from 210,000 km
The EA288 evo uses a wet timing belt (in oil bath) to drive the oil pump. If not replaced at the prescribed interval (approx. 210,000 km / 5 years, then every 90,000–100,000 km), it can fray unnoticed and leave rubber debris in the oil circuit — potentially damaging the turbocharger, camshaft adjuster and oil pump.
Symptoms: Fine black sludge residue or rubber particles visible at oil change; in advanced cases engine noises.
+ 3 more engine weaknesses + vehicle weaknesses
EA897 evo 3.0 TDI V6 with 48V mild hybrid — higher output stage of the EA897 evo in the upper mid-size class. 4 timing chains. Camshaft material defect (sev:5) as all EA897. From ECU MD1CS014 (07/2020): oil pressure problem — electronic pump reduces to ~1 bar up to 2,100 rpm. 48V MHEV with belt starter generator (recall 27H2, 2017–2020). Chain from 150,000 km. CR pump belt every 120,000 km. HP pump failure contaminates all 6 injectors. Launch hesitation with S-Tronic/Tiptronic (TPI 2060454/1). Effortless cruiser, but budget for EA897 maintenance. Oil every 10,000 km.
- !! Timing chain wear V6 TDI from 100,000 km
Like all EA897 variants, the DTPA has four timing chains that wear prematurely with poor maintenance. Timing chain repair costs several thousand euros.
Symptoms: Rattling and clattering on cold start, timing chain warning in instrument cluster - !! Camshaft material defect 3.0 TDI 257 hp from 80,000 km
EA897 EVO 257-hp variants are also affected by camshaft material defects. Audi replaces as goodwill with full service history, but recurrence after replacement has been documented.
Symptoms: Tapping, knocking engine noises of unusual intensity, power drop - !! Complex 4-chain timing drive from 120,000 km
Four timing chains in the EA897 (facelift version 2016+): one per cylinder bank, one connecting chain, one for the oil pump. Full replacement takes 15–20 hours, costs approx. €3,000.
Symptoms: Rattling on cold start, engine warning light (camshaft sensor fault)
+ 3 more engine weaknesses + vehicle weaknesses
The high-performance V6 diesel of this engine family combines a conventional exhaust turbocharger with an electrically driven auxiliary compressor fed by a 48-volt electrical system, which eliminates turbo lag at low revs. The compressor responds in under 250 milliseconds, spins up to 70,000 rpm and supports boost pressure down to just above idle speed – a bypass valve switches between the exhaust turbocharger and the auxiliary compressor once exhaust flow alone is sufficient. The valvetrain drive consists of two chains – a main chain for the four camshafts and a second one for the injection pump and ancillaries. The camshaft material defects of the early evo production batches lie years in the past for this late production stage. The factory oil pump control on this engine family deliberately lowers oil pressure under partial load, which can favour wear over the long term. EGR coking, particulate filter regeneration and AdBlue dosing remain routine maintenance topics even on this high-performance diesel.
- !! Camshaft fracture from material defect from 80,000 km
In the 3.0 TDI EA897 camshafts fracture due to material defects — affecting all four camshafts of the V6. A fracture inevitably causes engine damage. Audi acknowledged the issue via TPI 2043172.
Symptoms: Ticking or knocking engine noises beyond normal diesel sounds, then power loss and engine failure - !! Timing chain elongation — catastrophic engine damage possible from 120,000 km
The 3.0 TDI is prone to timing chain elongation and tensioner wear. A chain jump causes pistons and valves to collide, causing total engine damage. Replacement requires 15–20 labour hours.
Symptoms: Rattling or knocking on cold start and under load, engine stumbling, warning light - !! Soot deposits on injectors from 150,000 km
Diesel-typical soot formation on the 3.0 TDI injectors leads to injection problems and increased wear. Fuel additives and premium diesel can delay the need for cleaning.
Symptoms: Rough idle, increased consumption, hesitation under load, power loss at higher rpm
+ 2 more engine weaknesses + vehicle weaknesses
Mounted longitudinally, this was the first version of this output class before the facelift, built as a mild hybrid with a belt-driven 12-volt starter-generator for stop-start and mild recuperation. Cars fitted with this system and built between May 2017 and March 2020 are covered by the official recall campaign 27H2: moisture can enter the starter-generator and create short-circuit bridges that overheat it, so the recall has the component replaced outright at the workshop. Separately, the timing chain shows first wear on the hydraulic tensioner after roughly 80,000 to 90,000 kilometers, felt as a brief rattle after cold start. The oil pump traditionally struggles to build pressure at low revs. The plastic water pump and thermostat housing are a well-known leak point. The standard gasoline particulate filter clogs under pure short-trip driving, since it never reaches the 500 to 600 degree Celsius exhaust temperature needed for passive regeneration. Carbon deposits on the intake valves can't be ruled out with direct injection.
- !! Timing Chain Tensioner and Chain Wear from 120,000 km
The EA888 Gen3 has improved but not completely problem-free timing chain drive compared to earlier generations. Chain tensioners can wear from around 100,000–150,000 km. Early Gen3 variants show higher failure rates than later ones.
Symptoms: Metallic rattling on cold start (1–3 seconds), check engine light, with severe stretch power loss and rough running - !! Intake Valve Carbon Buildup from 80,000 km
As a direct injector without port injection, the EA888 Gen3 tends to intake valve coking. Newer versions with combined injection (PFI+DI) mitigate the problem. Walnut blasting every 80,000 km recommended.
Symptoms: Cold-start misfires, noticeable power loss in the mid-rpm range, rough running at low temperatures - !! Coolant Pump Leaking from 110,000 km
The EA888 Gen3 coolant pump can develop leaks or fail after 100,000–120,000 km. Early diagnosis prevents secondary damage from overheating.
Symptoms: Coolant level drops with no visible external leak, coolant smell from the engine bay, occasional overheating in city traffic
+ 2 more engine weaknesses + vehicle weaknesses
The higher-output version within this engine family's fourth generation, sharing compression ratio, direct injection and the belt-driven 12-volt starter-generator for stop-start and recuperation with the lower-output variant. The extra boost pressure and heat load put more strain on the turbocharger and timing chain, which is why sticking to the specified oil change intervals with the approved oil grade matters for chain longevity. The hydraulic tensioner loses pretension after standing still until full oil pressure returns — a brief rattle on cold start is normal, but a sustained noise is a warning sign. The plastic water pump and thermostat housing remain a known weak point across every output level of this generation and can fail completely. The gasoline particulate filter clogs under pure short-trip driving, since the 500 to 600 degree Celsius exhaust temperature needed for passive regeneration is never reached — regular runs under higher load prevent this. Carbon buildup on the intake valves is essentially unavoidable with direct injection.
- !! OPF Particulate Filter Clogged — Short-Trip Use from 80,000 km
The DMTA petrol particulate filter (OPF) requires regeneration cycles at sufficiently high exhaust temperatures. With frequent short-trip use or cold temperatures, the OPF cannot regenerate fully and clogs. Extended motorway drives often fix the problem.
Symptoms: Power loss, P200200 OPF efficiency fault, increased fuel consumption, MIL - !! Water Pump — Housing Failure from 120,000 km
EA888 evo uses an improved cooling system, but fundamentally the same water pump design. Early long-term experience still limited; the known Gen3/Gen3B plastic pump weakness is considered a risk.
Symptoms: Coolant loss, overheating warning, coolant smell - !! Timing Chain — Long-Term Experience Pending
EA888 evo has improved timing chain system over Gen3. Long-term experience from ~100,000 km still limited (market introduction 2020). Based on predecessor experience, chain inspection from 100,000 km remains recommended.
Symptoms: Rattling on cold start, P0016/P0017
+ 3 more engine weaknesses + vehicle weaknesses
Naturally aspirated by turbo alone V6 without a supercharger, direct injection, often paired with 48-volt support for recuperation and pull-away assistance. A brief timing chain clatter on cold start is not unusual — the hydraulic chain tensioner needs full oil pressure before it can hold the chain taut again; a persistent or louder noise belongs in a workshop. A known nuisance is the catalytic converter: if the ceramic substrate breaks down, dust enters the cylinders and causes misfires, usually accompanied by warning lights and a loss of power — documented cases show failures from around 65,000 kilometres onward, encouraged by poor fuel quality or chip tuning. As with any direct-injection engine, oil coking builds up on the intake valves over time since no fuel washes over them; walnut shell blasting from roughly 60,000 to 100,000 kilometres remedies this. On cars with the 48-volt system built between 2017 and 2020, it is also worth checking for a recall covering the belt starter generator due to possible moisture damage. Stick to oil change intervals and use only approved oil.
- !! Water Pump Internal Failure with Coolant in Vacuum System from 80,000 km
The EA839 DLZA (A6 C8, A7 4K, A8 D5) shares the known water pump weakness. Vacuum-controlled pump failure allows coolant to migrate into the vacuum system. Critical: 4-bolt pump still original, 6-bolt = already replaced.
Symptoms: Coolant warning light, coolant loss, P0299, 'drivetrain fault', start-stop disabled. - !! Rocker Arm Roller Failure — Early Production
Early EA839 variants with poor-quality rocker arm rollers (GP0) are also possible in the DLZA. Rollers can fall out and cause camshaft and piston damage.
Symptoms: Combustion misfire, knocking from cylinder head, engine fault light, rough running. - !! 48V Mild Hybrid Belt Starter-Generator Failure
The DLZA is fitted with a 48V MHEV. The belt starter-generator (BSG) and the 48V lithium-ion battery can fail. Control units before 2021 without moisture protection are vulnerable.
Symptoms: '48V system fault', rough starting, no recuperation, start-stop disabled, limp mode.
+ 4 more engine weaknesses + vehicle weaknesses
This plug-in hybrid drivetrain pairs a turbocharged four-cylinder with an electric motor integrated into the transmission and a lithium-ion high-voltage battery mounted in the underbody, representing the first battery generation offered. For part of the production run, an officially monitored recall is in effect because individual cell modules in the high-voltage battery can overheat during charging and, in rare cases, trigger a fire; suspected causes include deviations in cell manufacturing at a battery supplier. Affected vehicles receive a software update for battery monitoring that limits charging power or, where cell values are abnormal, results in a module or full battery replacement. Before buying, it is worth checking recall status via the VIN and reviewing the battery's health with diagnostic equipment. This early battery generation offers noticeably shorter pure electric range than the larger battery introduced later.
- !! Recall 93AB/93AD — High-Voltage Battery Overheating
Defective cell modules in the Samsung SDI high-voltage battery can overheat during charging and in extreme cases cause a vehicle fire. Affects Q5 and A6/A7 TFSI e production years 2019–2024. KBA recall 93AD.
Symptoms: Warning message in instrument cluster for high-voltage battery; charging process aborts; vehicle refuses external charging; in rare cases smell of burning. - !! Hybrid Gearbox Failure (S-Tronic 0D8/0D9) from 70,000 km
The S-Tronic hybrid gearbox shows premature failures on some TFSI e models. The PHEV gearboxes were developed under time pressure, leading to maturity issues on early examples.
Symptoms: Shift jerk on pull-away; gearbox shifts hesitantly or stays stuck in gear; gearbox fault message in instrument cluster; complete gearbox failure. - !! Timing Chain Elongation EA888 evo3 from 120,000 km
The EA888 evo3 timing chain can elongate excessively from around 100,000–130,000 km with neglected oil maintenance. Rattling on cold start and camshaft fault codes in the ECU are early signs.
Symptoms: Metallic rattling on cold start that subsides as engine warms up; engine fault codes P0016/P0017 (camshaft-crankshaft synchronisation); in advanced cases power loss.
+ 6 more engine weaknesses + vehicle weaknesses
This plug-in hybrid drivetrain pairs a turbocharged four-cylinder with an electric motor integrated into the transmission and a lithium-ion high-voltage battery mounted in the underbody, representing the first battery generation offered. For part of the production run, an officially monitored recall is in effect because individual cell modules in the high-voltage battery can overheat during charging and, in rare cases, trigger a fire; suspected causes include deviations in cell manufacturing at a battery supplier. Affected vehicles receive a software update for battery monitoring that limits charging power or, where cell values are abnormal, results in a module or full battery replacement. Before buying, it is worth checking recall status via the VIN and reviewing the battery's health with diagnostic equipment. This early battery generation offers noticeably shorter pure electric range than the larger battery introduced later.
- !! Recall 93AB/93AD — High-Voltage Battery Overheating
Defective cell modules in the Samsung SDI high-voltage battery can overheat during charging and in extreme cases cause a vehicle fire. Affects Q5 and A6/A7 TFSI e production years 2019–2024. KBA recall 93AD.
Symptoms: Warning message in instrument cluster for high-voltage battery; charging process aborts; vehicle refuses external charging; in rare cases smell of burning. - !! Hybrid Gearbox Failure (S-Tronic 0D8/0D9) from 70,000 km
The S-Tronic hybrid gearbox shows premature failures on some TFSI e models. The PHEV gearboxes were developed under time pressure, leading to maturity issues on early examples.
Symptoms: Shift jerk on pull-away; gearbox shifts hesitantly or stays stuck in gear; gearbox fault message in instrument cluster; complete gearbox failure. - !! Timing Chain Elongation EA888 evo3 from 120,000 km
The EA888 evo3 timing chain can elongate excessively from around 100,000–130,000 km with neglected oil maintenance. Rattling on cold start and camshaft fault codes in the ECU are early signs.
Symptoms: Metallic rattling on cold start that subsides as engine warms up; engine fault codes P0016/P0017 (camshaft-crankshaft synchronisation); in advanced cases power loss.
+ 6 more engine weaknesses + vehicle weaknesses
This revised stage of the plug-in hybrid drivetrain received a noticeably larger lithium-ion battery in the underbody compared with the first generation, meaningfully extending pure electric range and additionally enabling a charge mode that tops up the battery while driving, without changing the battery's physical footprint. Vehicles with this drivetrain are also covered by an officially monitored recall concerning individual high-voltage battery cell modules that can overheat during charging and, in the worst case, trigger a fire in the battery compartment. As part of the recall, a workshop installs a software update for battery monitoring that displays a warning message on the instrument cluster when anomalies are detected and automatically reduces charging power; in pronounced cases, the battery or an individual module is replaced entirely. Before buying, recall status should be checked via the VIN.
- !! Recall 93AD — high-voltage battery overheating
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. - !! Hybrid gearbox problems S-Tronic from 60,000 km
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. - !! Timing chain stretch EA888 evo4 from 130,000 km
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.
+ 5 more engine weaknesses + vehicle weaknesses
This plug-in hybrid drivetrain pairs a turbocharged four-cylinder with an electric motor integrated into the transmission and a lithium-ion high-voltage battery mounted in the underbody, representing the first battery generation offered. For part of the production run, an officially monitored recall is in effect because individual cell modules in the high-voltage battery can overheat during charging and, in rare cases, trigger a fire; suspected causes include deviations in cell manufacturing at a battery supplier. Affected vehicles receive a software update for battery monitoring that limits charging power or, where cell values are abnormal, results in a module or full battery replacement. Before buying, it is worth checking recall status via the VIN and reviewing the battery's health with diagnostic equipment. This early battery generation offers noticeably shorter pure electric range than the larger battery introduced later.
- !! Recall 93AB/93AD — High-Voltage Battery Overheating
Defective cell modules in the Samsung SDI high-voltage battery can overheat during charging and in extreme cases cause a vehicle fire. Affects Q5 and A6/A7 TFSI e production years 2019–2024. KBA recall 93AD.
Symptoms: Warning message in instrument cluster for high-voltage battery; charging process aborts; vehicle refuses external charging; in rare cases smell of burning. - !! Hybrid Gearbox Failure (S-Tronic 0D8/0D9) from 70,000 km
The S-Tronic hybrid gearbox shows premature failures on some TFSI e models. The PHEV gearboxes were developed under time pressure, leading to maturity issues on early examples.
Symptoms: Shift jerk on pull-away; gearbox shifts hesitantly or stays stuck in gear; gearbox fault message in instrument cluster; complete gearbox failure. - !! Timing Chain Elongation EA888 evo3 from 120,000 km
The EA888 evo3 timing chain can elongate excessively from around 100,000–130,000 km with neglected oil maintenance. Rattling on cold start and camshaft fault codes in the ECU are early signs.
Symptoms: Metallic rattling on cold start that subsides as engine warms up; engine fault codes P0016/P0017 (camshaft-crankshaft synchronisation); in advanced cases power loss.
+ 6 more engine weaknesses + vehicle weaknesses
This revised stage of the plug-in hybrid drivetrain received a noticeably larger lithium-ion battery in the underbody compared with the first generation, meaningfully extending pure electric range and additionally enabling a charge mode that tops up the battery while driving, without changing the battery's physical footprint. Vehicles with this drivetrain are also covered by an officially monitored recall concerning individual high-voltage battery cell modules that can overheat during charging and, in the worst case, trigger a fire in the battery compartment. As part of the recall, a workshop installs a software update for battery monitoring that displays a warning message on the instrument cluster when anomalies are detected and automatically reduces charging power; in pronounced cases, the battery or an individual module is replaced entirely. Before buying, recall status should be checked via the VIN.
- !! Recall 93AD — high-voltage battery overheating
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. - !! Hybrid gearbox problems S-Tronic from 60,000 km
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. - !! Timing chain stretch EA888 evo4 from 130,000 km
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.
+ 5 more engine weaknesses + vehicle weaknesses
The third-generation EA825: technically identical at its core to the Lamborghini Urus and Porsche Cayenne Turbo. 600 PS, cylinder deactivation (4 of 8 at part load), 48V mild hybrid with belt starter-generator, rear-wheel steering. This makes this C8 flagship surprisingly agile despite weighing over 2.1 tonnes. C7 owners report slightly duller throttle response in stock form — ECU/TCU mapping is often updated. Alternator fails unexpectedly early under high-performance use: 30,000–50,000 km lifespan documented on some examples. Engine itself has no characteristic weaknesses under normal use.
- !! Turbo Oil Strainer Clogged — Bearing Starvation from 80,000 km
Excessively fine-mesh oil strainer in the turbo oil supply clogs with carbon deposits. Result: turbo bearing starvation, turbo damage up to engine failure. Recall 21H7 (April 2022) affects production June 2012–March 2017.
Symptoms: Power loss, misfires, turbo whistling, oil burning - !! Timing Chain Elongated — Camshaft Synchronisation from 175,000 km
From around 150,000–200,000 km, timing chains can stretch or guide rails break. Camshaft-to-crankshaft synchronisation fault codes appear. Without repair, severe engine damage follows.
Symptoms: Rattling noise on cold start, rough idle, engine check light, camshaft fault codes - !! Turbo Oil Drain Lines Coked — Shaft Seal Failure from 150,000 km
Hot-V mounted turbos tend to oil carbon buildup in drain lines when frequently shut down after full-load without cooldown time. Coking leads to turbo oil loss and bearing damage without immediate symptoms.
Symptoms: Blue smoke after parking, turbo bearing whine at high rpm, slowly increasing oil consumption, eventually power loss
+ 7 more engine weaknesses + vehicle weaknesses
Performance variant of the C8 4.0 TFSI — noticeably more power than the DCSA through sharper turbos and more aggressive mapping. Owners describe the jump from standard to Performance as dramatic: 'a different beast, too quick'. The oil strainer issue from the CWUB/CRDB is resolved in the DJTB through a redesigned strainer. The OPF remains, but the Performance exhaust with larger tailpipes and active valves delivers somewhat more volume than the standard. Rear-wheel steering standard — it makes the over 2.1-tonne estate surprisingly agile in tight corners.
- !! Turbocharger Bearings — Thermal Stress in V-Position from 120,000 km
The turbos sit in the hot V-space between the cylinder banks, which leads to elevated thermal stress. With spirited use or insufficient post-run cooldown times, increased bearing wear results.
Symptoms: Whistling, oil burning (blue smoke), power loss at high rpm - !! Turbocharger Oil Supply — Strainer and Drain Lines from 100,000 km
Even on the performance DJTB, the oil supply to the Hot-V turbos remains critical. Revised oil strainer (079115175G) must be fitted. Drain lines tend to coking under high-performance use.
Symptoms: Turbo whistling, power loss after extended full-throttle phase, blue smoke after shutdown, oil in charge air area - !! 48V Electrical System and Mild Hybrid Components Fault-Prone from 40,000 km
The DJTB (RS6 C8, RS7 C8, RS Q8) shows failures in the 48-volt system. Reports confirm defects at 20,000–70,000 km in batches, sometimes multiple vehicles at the same workshop simultaneously.
Symptoms: Electrical system warnings, power reduction, mild hybrid system fault, service warning light
+ 7 more engine weaknesses + vehicle weaknesses
EA839 2.9 TFSI V6 twin-turbo with 331 kW — high-performance engine of the C8 generation. Two turbochargers, timing chain, direct injection. From ECU MD1CS014: identical oil pressure problem as all EA839/EA897 evo. Turbos between cylinder banks (hot-V) — extreme heat, wear from 60,000–80,000 km. Chain with cold-start clatter. S-Tronic DL382: oil every 60,000 km, launch judder, mechatronic defects. Cat disintegration with chip tuning. 48V MHEV with RSG — check recall 27H2. Camshafts factory-paired. Running a twin-turbo V6 with hot-V and MHEV is a commitment. Oil every 10,000 km, 5W-30 low-SAPS.
- !! Rocker Arm Roller Bearing Failure — Engine Damage from 60,000 km
Small roller bearings in the rocker arms can detach and fall into the oil pan. Affects 2.9 BiTurbo engines from early production (up to approx. 2019, code GP0). Revised rocker arms (GP1) introduced from 2017.
Symptoms: Knocking noises from cylinder head, engine roughness, misfires, metal particles in the oil - !! Upper Chain Tensioners Defective — Rattling from 80,000 km
The upper timing chain tensioners of the 2.9 TFSI tend to weaken. Typical rattling on cold start that disappears after warm-up. Audi revised the tensioners; goodwill repair often possible.
Symptoms: Rattling on cold start (2,000–3,000 rpm), disappears after warm-up - !! High-Pressure Pump Defective from 80,000 km
The DCTB 2.5 TFSI Evo (RS3 8Y, 400 hp) shows early high-pressure pump failure on some examples. Power loss and misfires are typical symptoms.
Symptoms: Power loss under high load, rough running, fault code fuel pressure control, increased fuel consumption.
+ 2 more engine weaknesses + vehicle weaknesses
EA839 2.9 TFSI V6 twin-turbo with 331 kW — high-performance engine of the C8 generation. Two turbochargers, timing chain, direct injection. From ECU MD1CS014: identical oil pressure problem as all EA839/EA897 evo. Turbos between cylinder banks (hot-V) — extreme heat, wear from 60,000–80,000 km. Chain with cold-start clatter. S-Tronic DL382: oil every 60,000 km, launch judder, mechatronic defects. Cat disintegration with chip tuning. 48V MHEV with RSG — check recall 27H2. Camshafts factory-paired. Running a twin-turbo V6 with hot-V and MHEV is a commitment. Oil every 10,000 km, 5W-30 low-SAPS.
- !! Rocker Arm Roller Bearing Failure — Engine Damage from 60,000 km
Small roller bearings in the rocker arms can detach and fall into the oil pan. Affects 2.9 BiTurbo engines from early production (up to approx. 2019, code GP0). Revised rocker arms (GP1) introduced from 2017.
Symptoms: Knocking noises from cylinder head, engine roughness, misfires, metal particles in the oil - !! Upper Chain Tensioners Defective — Rattling from 80,000 km
The upper timing chain tensioners of the 2.9 TFSI tend to weaken. Typical rattling on cold start that disappears after warm-up. Audi revised the tensioners; goodwill repair often possible.
Symptoms: Rattling on cold start (2,000–3,000 rpm), disappears after warm-up - !! High-Pressure Pump Defective from 80,000 km
The DCTB 2.5 TFSI Evo (RS3 8Y, 400 hp) shows early high-pressure pump failure on some examples. Power loss and misfires are typical symptoms.
Symptoms: Power loss under high load, rough running, fault code fuel pressure control, increased fuel consumption.
+ 2 more engine weaknesses + vehicle weaknesses
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| Recall: Panoramic Roof Can Detach Contamination of the bonding surface during manufacture can cause the rear panoramic roof module to detach. Affects A6 models produced in 2018. Symptoms: Wind noise, leaks at sunroof; in extreme cases rear glass panel detaches at speed | Low | |
| Recall: Panoramic Roof Bonding Defective On the A6 Avant (MY 2018), the rear glass panel of the panoramic roof was incorrectly bonded. Audi recalled 1,435 vehicles in Germany. Creaking/scraping noises and water ingress are further known issues with the panoramic roof. Symptoms: Creaking or scraping noises from roof area, wind noise from panoramic roof, possible water ingress in rain. | High | |
| Recall: PHEV Battery Overheating Risk During Charging 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. Symptoms: Unusual smells or heat generation during charging. | Low | |
| Recall: BSG moisture ingress — fire risk Moisture enters 48V starter generator → electrical short → fire risk. Affects 2019–2020 builds. Free replacement at dealer. Symptoms: No warning — preventive recall | Low | |
| Recall: The cell modules of the HV battery may overheat during the charging process… The cell modules of the high-voltage battery may overheat during the charging process. There is a risk of fire. | ||
| Recall: During the charging process, a defect in the battery modules may cause the HV battery to… During the charging process, a defect in the battery modules may cause the high-voltage battery to overheat. This can lead to a fire and injuries to occupants and bystanders. | ||
| AdBlue/SCR system — engine lockout on failure (diesel) All Euro 6 diesels have SCR. On failure, engine lockout after ~1,000 km. NOx sensor €200–600, urea pump up to €1,500, complete AdBlue tank up to €4,000. Symptoms: AdBlue warning, countdown to engine lockout, NOx/dosing valve fault codes from 80,000 km | High |
Test Reports
Vehicle inspection (HU)
Few defects, good results for the age bracket
2024Top Reported Issues
Alternatives
Explore more
Known Problems and Issues +
A total of 113 weaknesses have been documented for the Audi A6 C8 (2018–2024) — 102 engine-related and 11 vehicle-related. 2 problem engines: DDVE (3.0L TDI V6), DMKD (3.0L TDI V6). Typical issues affect Other, Electronics, Body, Suspension. Considered reliable: DMTA (2.0L TFSI).
A6 (DLBA, 2018–2020) — Be Careful: Timing Chain Tensioner and Chain Wear, Intake Valve Carbon Buildup, Coolant Pump Leaking. Power: 245–252 PS.
A6 (DLZA, 2018–2024) — Be Careful: Water Pump Internal Failure with Coolant in Vacuum System, Rocker Arm Roller Failure — Early Production, 48V Mild Hybrid Belt Starter-Generator Failure. Power: 333–340 PS.
A6 (DCSA, 2019–2024) — Be Careful: Turbo Oil Strainer Clogged — Bearing Starvation, Timing Chain Elongated — Camshaft Synchronisation, Turbo Oil Drain Lines Coked — Shaft Seal Failure. Power: 600 PS.
A6 (DCTB, 2019–2024) — Be Careful: Rocker Arm Roller Bearing Failure — Engine Damage, Upper Chain Tensioners Defective — Rattling, High-Pressure Pump Defective. Power: 450 PS.
A6 (DJTB, 2023–2024) — Be Careful: Turbocharger Bearings — Thermal Stress in V-Position, Turbocharger Oil Supply — Strainer and Drain Lines, 48V Electrical System and Mild Hybrid Components Fault-Prone. Power: 630 PS.
A6 (DLGA, 2021–2023) — Be Careful: Recall 93AB/93AD — High-Voltage Battery Overheating, Hybrid Gearbox Failure (S-Tronic 0D8/0D9), Timing Chain Elongation EA888 evo3. Power: 245–252 PS.
A6 (DRYA, 2021–2025) — Be Careful: Recall 93AD — high-voltage battery overheating, Hybrid gearbox problems S-Tronic, Timing chain stretch EA888 evo4. Power: 265 PS.
A6 (DEZE, 2018–2024) — Be Careful: EGR Cooler Crack and Coolant Loss, Wet Timing Belt Premature Wear, Turbocharger Secondary Damage from DPF/EGR. Power: 163 PS.
A6 (DFBA, 2018–2024) — Be Careful: EGR cooler leak and coolant loss, Wet timing belt in oil bath — wear, Oil consumption EA288 Evo piston rings. Power: 204 PS.
A6 (DDVE, 2018–2020) — Stay Away!: Camshaft fracture — 272 hp, Timing chain elongation — V6 TDI 272 hp, High-pressure pump failure — system contamination. Power: 231 PS.
A6 (DDVB, 2018–2019) — Be Careful: Timing chain rattles on cold start, Camshaft fracture — material defect, AdBlue system: pump and injector failure. Power: 286 PS.
A6 (DEWA, 2019–2020) — Be Careful: Timing chain wear V6 TDI, Camshaft material defect 3.0 TDI 257 hp, Complex 4-chain timing drive. Power: 344–349 PS.
A6 (DEZF, 2019–2024) — Be Careful: Recall: Belt Starter-Generator Fire Risk (KBA 9831), 48V Belt Starter-Generator Failure (Battery Deep-Discharge), Wet Timing Belt — Scheduled Wear Item. Power: 136 PS.
A6 (DMGA, 2020–2024) — Be Careful: Timing chain rattles on cold start, Camshaft fracture — material defect, AdBlue system: pump and injector failure. Power: 286 PS.
A6 (DMKD, 2020–2024) — Stay Away!: Camshaft fracture from material defect, Timing chain elongation — catastrophic engine damage possible, Soot deposits on injectors. Power: 340–349 PS.
What to watch out for with the Audi A6? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
What problems and weaknesses does the Audi A6 C8 have? +
What should I look for when buying a used Audi A6 C8? +
Which engine is recommended? +
Which Audi A6 C8 engine is the most reliable? +
Which Audi A6 C8 engine is the most fun? +
Is the Audi A6 C8 worth buying used? +
What horsepower variants are available for the Audi A6 C8? +
Last updated: February 2026 · All information without guarantee