The most powerful V8 petrol in the D4-generation A8, though not the range topper, since the A8 L W12 produced 500 PS. It pairs a twin-turbo V8 with Audi's aluminium space frame chassis and adaptive air suspension. The hot-V engine layout places the turbochargers between the cylinder banks for compact packaging and quick response. Pre-facelift models (CEUA, 420 hp) ran from 2012-2013, while post-facelift models (CTGA, 435 hp) continued through 2017. Heavy depreciation makes these available for a fraction of the original price, but the V8 twin-turbo complexity and flagship electronics keep running costs firmly in premium territory.· more· less
Powerful, refined twin-turbo V8Aluminium body resists corrosion
Buy if: You want flagship V8 luxury with strong performance and can find a well-maintained example with verified turbo oil screen service and complete Audi service history.
Avoid if: You cannot budget for surprise repair bills in the €2,000-5,000 range or the car has incomplete service records and unverified recall status.
Factory oil screen between cylinder banks clogs, starving turbochargers of lubrication · more· less
The 4.0 TFSI has a small mesh oil filter screen located deep in the engine valley that filters oil before it reaches the turbochargers. This screen clogs over time, restricting oil flow and eventually starving the turbos of lubrication. Audi acknowledged this with TSB 21 18 30 2044640, addressing turbocharger damage on 2013-2017 models. If caught early, cleaning or replacing the screen plus oil lines costs around €750-1,500 at a specialist. If the turbochargers are already damaged, expect €3,000-5,000 for a turbo rebuild at a specialist, or up to €8,000 at an Audi dealer with new turbochargers and manifolds. Aftermarket solutions like the JHM relocatable strainer kit (around €500) move the filter to an accessible location for regular servicing. This is the most critical issue to verify before purchase.
Active engine mount failure
up to €1,5002 of 8
Electronically controlled engine mounts fail, causing noticeable vibrations at idle and low RPM · more· less
The A8 4.0 TFSI uses active (electronically controlled) engine mounts that dampen engine vibrations. These are known to fail, causing heavy vibrations felt in the cabin, particularly at idle and between 1,000-3,000 rpm. Audi's bulletin 2036392 is often quoted as evidence of defective mount hardware, which it is not: it prescribes optimised control software for the J931 mount controller and, if vibration persists, transmission adaptation and revised exhaust downpipes rather than new mounts. Genuinely failed mounts are a separate matter and do occur. Replacement parts cost around €300-500 each, with two mounts typically needed. Labor runs approximately €300-500 due to accessibility challenges. After replacement, the mounts may need to be recalibrated via VCDS diagnostic software. Most failures occur between 60,000-120,000 km.
Air suspension strut leak or compressor failure
up to €3,5003 of 8
Air springs develop leaks and the compressor wears out from overwork, causing the car to sag · more· less
The D4 A8 uses adaptive air suspension on all four corners. Air springs (bellows) typically develop leaks after 80,000-120,000 km, causing one corner or the entire car to sag overnight. A single air strut costs €500-800 for an OEM-quality aftermarket unit from suppliers like Arnott or Aerosus, plus €200-400 labor. The compressor typically fails as a secondary consequence of a leaking spring (it runs constantly trying to maintain pressure). Compressor replacement costs €400-600 for the part plus €200-300 labor. The compressor relay should always be replaced alongside the compressor to prevent premature failure of the new unit. Budget for at least one strut and potentially a compressor over the ownership period.
Coolant line and thermostat housing leaks
up to €2,5004 of 8
Coolant valves and thermostat housing develop leaks, risking overheating and ECU damage · more· less
The 4.0 TFSI has documented coolant system weak points. Coolant control valves (N488 and N509) can leak, allowing coolant to reach the engine control module and cause electrical damage. Audi recalled US-market cars built 15 May 2010 to 14 May 2012 for this issue; no general European campaign is documented. The thermostat housing and associated O-rings also develop leaks, particularly on the turbocharger coolant lines. Audi issued a technical service bulletin and a US and Canadian service action addressing damaged O-rings in turbocharged coolant lines for 2013-2014 models. Thermostat housing replacement costs around €600-1,000 including labor. Coolant valve replacement runs €300-500. If coolant has damaged electronic components, costs can escalate significantly to €1,500-2,500.
PCV valve / engine oil separator failure
up to €8005 of 8
Crankcase ventilation valve degrades, causing rough idle, oil smell, and excessive oil consumption · more· less
The positive crankcase ventilation system is a known wear point on the 4.0 TFSI. The PCV valve or engine oil separator can fail, causing rough idle, misfires, a whistling noise from the engine bay, and oil smell. The hot-V layout accelerates degradation due to heat exposure. Symptoms include lean air-fuel ratio fault codes (P0171, P2187) and blue exhaust smoke from oil carryover. The part costs approximately €150-250 and labor around €200-400. Recommended inspection interval is every 60,000 km. Proactive replacement before symptoms appear prevents secondary damage.
Timing chain tensioner wear
up to €6,0006 of 8
Chain tensioner weakens with age and mileage, causing cold start rattle and risk of chain skip · more· less
While less prevalent than on the smaller 2.0 TFSI engines, timing chain tensioner wear has been reported on the 4.0 TFSI, particularly on early CEUA-coded engines and high-mileage examples beyond 120,000 km. The tensioner can lose hydraulic pressure overnight, resulting in a brief rattle on cold startup. If the chain skips teeth, catastrophic valve damage can result. The repair is labor-intensive because the engine must come out of the car for the 4.0T, bringing costs to €3,000-4,500 at a specialist or €5,000-6,000 at a dealer. This is a less common issue than the turbo oil screen problem but far more expensive when it occurs.
MMI infotainment screen and module failure
up to €2,0007 of 8
The motorized pop-up MMI screen or its control module can malfunction with age · more· less
The D4 A8 uses a motorized pop-up MMI screen that is known to develop mechanical and electronic faults. The screen motor can fail, preventing the display from opening or closing properly. The MMI control module itself can also fail, causing blank screens, freezing, or loss of navigation. Due to Audi's Component Protection system, replacement modules must be coded to the specific vehicle, adding cost. Screen repair or replacement runs €500-1,200, while a full MMI module replacement at a dealer can reach €1,500-2,000. Used modules with coding service are available for €300-600.
ZF 8HP transmission adaptation issues
up to €2,0008 of 8
The 8-speed automatic can develop jerky shifting if fluid is old or mechatronic sleeves are worn · more· less
The ZF 8HP transmission is fundamentally reliable, but can develop rough or jerky shifting if the fluid has not been changed. Despite Audi marketing the fluid as lifetime fill, ZF recommends a fluid and filter service every 100,000 km. Neglected transmissions develop harsh downshifts and lurching behavior. A fluid and filter service costs €400-600 and often resolves shifting issues. In more severe cases, worn mechatronic sleeves or solenoids require replacement, costing €1,000-2,000. After any service, the transmission adaptation values should be reset via VCDS for smooth shifting.
Complex flagship with known engine-specific weak points
The 4.0 TFSI V8 is fundamentally robust, and many examples exceed 150,000 km without major powertrain failure. However, the hot-V layout creates specific maintenance demands around the turbo oil feed, coolant system, and PCV components. The turbo oil screen clogging issue is the most critical concern and should be verified as addressed before purchase. Air suspension adds a layer of cost common to all D4 A8 models. Meticulous service history with documented oil changes and coolant system inspections is essential for a reliable ownership experience.
Service history
Complete Audi dealer or specialist records essential. Verify oil change frequency (every 15,000 km or annually for this engine).
Tires and alignment
Check tread depth, age (date codes), and uneven wear. Misalignment is common after air suspension repairs.
Cold start
Must start engine completely cold. Listen carefully for rattling from the timing chain area in the first 10-30 seconds.
Extended test drive
Minimum 30 minutes including highway and city driving. Get the transmission and engine up to full operating temperature.
Specific for this vehicle
Verify turbo oil screen service or recall status
This is the single most important check. Ask if the turbo oil feed screen has been cleaned, replaced, or upgraded (TSB 2044640). Request documentation. If unverified, budget for immediate inspection.
Check for engine vibrations at idle
With engine running and in park, feel for excessive vibrations through the steering wheel and dashboard. Active engine mount failure causes noticeable shaking at idle.
Test all air suspension modes
Switch between Comfort, Auto, and Dynamic modes over uneven surfaces. Leave the car parked for at least 15 minutes and check if it sags on one side. Listen for the compressor running constantly.
+ 4 more checksShow less
Inspect coolant level and system for leaks
Check coolant reservoir level and look for signs of leaks around the turbo area, thermostat housing, and underneath the intake manifold. Brown or milky coolant indicates contamination.
Test MMI screen operation
Open and close the motorized MMI screen several times. Test all infotainment functions, navigation, Bluetooth, and camera systems.
Check oil consumption history
Ask the owner about oil consumption between services. More than 0.5 liter per 1,000 km suggests PCV or piston ring issues. Check for blue exhaust smoke on startup and hard acceleration.
Run full diagnostic scan with VCDS
Scan all control modules for stored and pending fault codes. Pay particular attention to engine, transmission, and air suspension modules. Check adaptation values for the transmission.
Recalls and Technical Service Bulletins
Turbocharger oil strainer can restrict oil supply (European recall, April 2022; covers 2012-2017 cars)Critical - verify completed
Engine compartment seal fire risk (European recall, October 2020; covers the D4 4.0 TFSI)Critical - verify completed
Sunroof glass shattering (European recall, March-July 2013 build window with the standard sunroof)Verify completed
Takata airbag inflator (varies by production date)Verify with VIN
Contact an Audi dealer with the VIN to verify these have been completed. The two that matter most for the 4.0 TFSI are the April 2022 turbocharger oil strainer recall, covering 2012-2017 cars, and the October 2020 engine compartment seal recall for fire risk. Note the sunroof window is narrow, March to July 2013 production, not every 2013-2014 car. Items often quoted for this engine are American: an NHTSA recall covers A8s built 15 May 2010 to 14 May 2012 in the United States and is not evidence of a general European campaign, and service action for the turbocharger coolant line O-rings was explicitly a US and Canada action.
Warranty Status
Factory warranty (2-3 years by market)Expired on all D4 models; 2 years in Germany, up to 3 years or 60,000 miles on UK-supplied cars
Rust perforation warranty (12 years)May still apply to 2014+ models
Extended warrantyAudi's approved used programmes have an 8-year entry limit, which every D4 now exceeds
All D4 A8 models are outside their original factory warranty, which ran 2 years in Germany and up to 3 years or 60,000 miles on UK-supplied cars. Audi's 12-year rust perforation warranty may still apply to later models. Do not count on enrolling one of these in an official approved-used warranty: both the UK and German programmes impose an eight-year entry limit that every 2012-2017 D4 now exceeds, although cover already running may continue on its own terms. For a car of this complexity, an extended warranty or inspection-based guarantee from a reputable dealer is strongly recommended.
Sources: Research draws on model-specific owner forums and owner communities, recall information from official authorities, German automotive press, and multiple workshop cost references cross-checked against each other.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.
