Water Pump and thermostat has a faulty design that causes coolant to leak either around the O Ring and/or the elbow. I am in my third water pump and thermostat with only 69,000 miles on the vehicle. Issue appears to be common on the EA824 (4.0 twin turbo) engine with hundreds of reports from the complete range of EA824 equipped vehicles (S8, RS7, S6, S7, A8 etc). Average mileage of those reported are 65k miles or so. Hundreds of similar issues are reported via various Audi forums and social media groups. Poses a fire risk since coolant leaks all over the front of the engine. Poses another safety risk if the engine seizes due to overheating while in motion. Either would be catastrophic
The worst 2015 Audi S8 problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
- Engine5
- Transmission1
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
- Engine5
- Transmission1
Recalls 4
Engine and engine cooling: engine: gasoline: turbo/supercharger
- What is wrong
- Volkswagen Group of America, Inc. (Audi) is recalling certain 2013-2017 A8, S6 Sedan, S7, S8, and 2014-2017 RS7 vehicles. The turbocharger oil supply strainer can become blocked, causing wear to the bearings due to lack of lubrication.
- Risk
- Worn bearings can cause the turbine wheel to contact the turbocharger housing or cause the shaft to break, causing an engine stall and increasing the risk of a crash.
- Remedy
- Dealers will replace the oil strainer and perform an oil change, free of charge. Owner notification letters were mailed August 4, 2022. Owners may contact Audi customer service at 1‑800‑253‑2834. Audi's number for this recall is 21H7.
Recall number 22V178000 · Recall details
Structure: body: hood
- What is wrong
- Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2018 Audi S8 and A8 vehicles. The seal around the engine compartment may come loose and contact hot engine components.
- Risk
- If the seal contacts hot engine components, there could be an increased risk of a fire.
- Remedy
- Audi will notify owners, and dealers will install a retaining plate to prevent the engine compartment seal from loosening. The recall began September 4, 2020. Owners may contact Audi customer service at 1‑800‑253‑2834. Volkswagen's number for this recall is 51G6.
Recall number 20V397000 · Recall details
Fuel system, gasoline: delivery: hoses, lines/piping, and fittings
- What is wrong
- Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2016 Audi A8 and S8 vehicles. The fuel supply line for the high pressure fuel pump may become porous and leak fuel.
- Risk
- Leaking fuel, in the presence of an ignition source, increases the risk of fire.
- Remedy
- Audi has notified owners, and dealers will install a fuel pressure damper, free of charge. The recall began February 21, 2019. Owners may contact Audi customer service at 1‑800‑253‑2834. Volkswagen's number for this recall is 20BM.
Recall number 19V057000 · Recall details
Fuel system, gasoline: delivery: hoses, lines/piping, and fittings
- What is wrong
- Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2015 Audi S8 and A8 vehicles. The fuel supply line for the high pressure fuel pump may become porous over time, resulting in a fuel leak.
- Risk
- A fuel leak in the presence of an ignition source can increase the risk of a fire.
- Remedy
- Audi will notify owners, and dealers will replace the fuel line, free of charge. The recall began July 20, 2018. Owners may contact Audi customer service at 1‑800‑253‑2834. Volkswagen's number for this recall is 20AV.
Recall number 18V430000 · Recall details
See all 4 recalls for the 2015 Audi S8
Defect investigations
Engine Stall - Turbo Failure
On March 29, 2021, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE 21-009) after the agency received 58 reports alleging engine stalling in 2013-2016MY Audi vehicle models A8, S6, S7, S8 & RS7 equipped with the 4.0L, twin-turbocharged engine. Complainants reported the vehicles would stall with no warning while driving at highway or city traffic speeds. Several of the complainants alleged an inability to restart. The complaints alleged the major contributing factor to the engine stalling was the failure of the turbochargers. The complaints cited the turbocharger failure was a result of oil starvation due to a clogged oil strainer in the turbocharger oil supply line.The location of the oil strainer in the turbocharger oil supply line is in the inner valley of the engine. It is not easily accessible, making servicing the component difficult. The oil strainer removes particles and carbon deposits from the oil before lubricating the turbochargers. Over time, if the debris is not removed from the oil strainer, it becomes clogged and prevents oil from flowing to the turbochargers. This causes the turbine bushings to run dry and overheat resulting in turbine shaft failure due to thermal stress.On April 04, 2022, PE21-009 was upgraded to an Engineering Analysis (EA22-001) to further assess the scope, frequency, and potential safety related consequences of the alleged defect. Volkswagen filed recall 22V‑178 to replace the 30?m mesh oil strainer with a 90?m mesh oil strainer in the subject vehicles. VW introduced the larger mesh oil strainer into production in March of 2017 effecting the 2017-2018MY vehicles.ODI reviewed information from VW for vehicles that had the larger mesh installed in production. The data received showed, since the new oil strainer size of 90?m went into production for the 2017-2018MY, there has not been any reported incidents of turbocharger failures due to oil starvation or other failures that could be related to the larger screen mesh. In view of the recall being conducted by VW and lack of any detrimental side effect to the turbocharger caused by the larger mesh, ODI is closing this Engineering Analysis (EA). The agency reserves the right to take additional action if warranted by future circumstances.11502847,11506565,11494663,11488813,11486393,11480926,11479882,11476289,11466761 11464663,11463254,11460580,11460496,11458973,11458804,11457556,11454753,11452668 11452589,11452584,11452383,11452175,11452111,11451724,11451724,11450995,11450988 11449661,11447092,11443657,11442867,11440536,11440052,11439959,11438691,11436461 11435619,11433925,11433733,11432336,11431661,11431421,11429704,11429584,11428128 11426929,11424203,11423603,11423337,11422431,11421084,11420626,11420342,11419693 11418884,11418437,11418433,11418135,11417635,11417351,11416095,11414578,11414235 11414064,11413359,11413285,11413214,11407510,11407450,11406897,11406821,11406637 11406460,11406416,11406291,11406287,11406277,11406273,11406263,11406256,11406251 11406229,11406222,11406208,11406204,11406197,11406182,11406015,11404665,11404426 11404348,11403823,11403430,11403268,11402684,11399435,11397821,11396241,11394763 11391037
EA22001
Engine Stall - Turbo Failure
On March 29, 2021, the Office of Defects Investigation (ODI) opened Preliminary Evaluation (PE) 21-009 after the agency received 58 reports alleging engine stalling in 2013-2016MY Audi vehicle models A8, S6, S7, S8 & RS7. The subject vehicles are equipped with 4.0L, twin-turbocharged engine. Complainants reported that the vehicles stall suddenly with no warning while driving on the highway or in city traffic. Several of the complainants alleged an inability to restart. The complaints allege the major contributing factor to the engine stalling is the failure of the turbochargers. The complaints further allege the turbocharger failure is a result of oil starvation due to a clogged oil strainer.The location of the oil strainer in the turbocharger oil supply line is in the inner valley of the engine. It is not easily accessible, making regular service difficult. The oil strainer removes dirty particles and carbon deposits from the oil before flowing to lubricate the Turbochargers. Overtime if the debris are not removed from the oil strainer, it clogs the strainer and prevents free flow of oil to the turbochargers and makes the turbine bushings to run dry and overheat which causes the turbine shaft to break due to thermal stress. In VW's response to ODI's Information Request letter, VW provided approximately 611 warranty claims with unique VINs, 70 Field Reports and 45 Consumer complaints. These reports allege engine stalling due to turbocharger failure similar to the federal safety agency reports described above. To date, the federal safety agency has received approximately 98 allegations of stall due to turbocharger failures. The total of 824 reports shown in the table above eliminates duplicate reports received by both ODI and the manufacturer.This Preliminary Evaluation is being upgraded to an Engineering Analysis (EA) to further assess the scope, frequency, and potential safety related consequences of the alleged defect of engine stalling due to turbocharger failureThe ODI complaints cited above can be viewed at under the following ODI identification numbers:11452589, 11452584, 11452383, 11450995, 11450988, 11449661, 11447092, 11442867 11440536, 11440052, 11439959, 11438691, 11436461, 11435619, 11431661, 11429704 11429584, 11426929, 11424203, 11423603, 11423337, 11421084, 11420626, 11420342 11418884, 11418437, 11418433, 11417635, 11417351, 11416095, 11414235, 11413359 11413214, 11413285, 11413133, 11407510, 11407450, 11407289, 11406821, 11406416 11406291, 11406277, 11406273, 11406256, 11406251, 11406229, 11406222, 11406204 11406197, 11406182, 11404665, 11404426, 11404348, 11403430, 11403268, 11399435 11397821, 11396241, 11394763, 11391037, 11388662, 11387166, 11377446, 11363283 11354107, 11344193, 11342497, 11342360, 11340302, 11325065, 11324163, 11322168, 11321144, 11318477, 11306754, 11279429, 11268109, 11256706, 11252723, 11246579 11234853, 11234714, 11231582, 11231013, 11230589, 11229484, 11222281, 11218822 11218749, 11217604, 11209168, 11209142, 11197149, 11191243, 11175842, 11170776 11164032, 11152418.
PE21009
Technical service bulletins for the 2015 Audi S8 696
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- This bulletin provides informaiton on the use of the PICO-NVH tool (VAS 611 015).
- This bulletin proides service information when there is a prompt to take over the steering wheel (hands...
- This bulletin provides information when the starter battery is discharged or malfunctioning.
- This bulletin provides information to aid in diagnosing the vehicle locking system.
- This bulletin provides information when the engine is not runing smoothly; all gas engines.
- This bulletin provides information on VIN plates, Safety Certification labels, and ordering procedures.
- This bulletin provides information for reporting safety related information to the manufacturer.
- This bulletin states that technicians are required to report to the manufacturer when a vehicle has...
- This bulletin provides service information regarding exterior glass cleaning.
- This bulletin provides information about vibrations and rotational steering vibrations.
What 2015 Audi S8 owners say
Most recent owner complaints, unedited.
The contact owns a 2015 Audi S8. The contact stated he was unable to start the vehicle. The contact stated that the Electronic Power Control (EPC) warning light was illuminated. The contact was able to start the vehicle, but the vehicle was shaking while driving. The contact also stated the vehicle had stalled. The contact took the vehicle to an independent mechanic and was informed that the oxygen sensor and oil pressure switch needed to be replaced. The vehicle was repaired but continued to experience the failure. The contact took the vehicle back to an independent mechanic and was referred to a local dealer. The contact called the local dealer and made them aware of the failure. The vehicle was not diagnosed or repaired. The VIN was associated with the federal safety agency Campaign Number: 22V178000 (Engine and Engine Cooling). The manufacturer had been informed of the failure. The failure mileage was approximately 116,000.
Turbo failure and positive crankcase ventilation (PCV) failure. Whining noise from PCV and smoke out the tail pipes with no power. Had to pay out of pocket to remedy issues.
Was driving on a saturday afternoon down a busy street when my car started sputtering and had very reduced power. I was able to eventually get to the side of the road and shut the car off. Tried starting the car after a resting period and car would not start. Let it sit longer and finally got it to start but car had very little power when pressing on the gas , but I was able to get to my local audi dealer for a diagnosis. ($190.00 + tax). I informed the technician of the issues I saw and also that I heard a whining noise coming from the engine. Diagnosis was that both turbos had significant "play" in them and they needed to be replaced. The tech said that this is caused by an oil screen deep inside the engine, which is a known cause of this issue. Price to repair would be $11,500.00!!!! If this is a known issue as audi states, why isn't this a recall issue, especially with the cost incurred by consumers?
Only 43,750 miles and the engine is being completely rebuilt. New cam adjusters, new timing chain tensioners, new timing chain guides... This shouldn't happen on a car with such few miles.
I was driving at highway speed when the engine suddenly started to shudder and lose power. The check engine light immediately started to flash and the engine stalled. I was stopped in a busy highway during rush hour. I eventually got the car to a safe location and pulled the turbo air intake to inspect the turbo with a borescope. The bank 1 turbo had damaged itself. This should not happen on a car with only 50,000 miles.
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Questions about the 2015 Audi S8
Is the 2015 Audi S8 reliable?
Owners have filed 6 complaints about the 2015 Audi S8, close to a typical S8 model year.
What is the most common problem with the 2015 Audi S8?
Engine and cooling, with 5 complaints. Next is transmission (1).
How many recalls does the 2015 Audi S8 have?
4 recalls, covering engine and engine cooling, structure and fuel system, gasoline.
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