Problems · NHTSA complaints
2015 Audi S8 problems
Owners filed 6 complaints about the 2015 Audi S8 with NHTSA between May 2018 and Mar 2024. The most-cited component is engine (5).
Complaints
6
Filed with NHTSA
Crashes
0
Reported by owners
Fires
0
Reported by owners
Injuries
0
People reported injured
Deaths
0
Reported to NHTSA
Complaints by component
One complaint can cite several components
- Engine5
- Power train1
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
Data from NHTSA Complaints API · synced Oct 29, 2026NHTSA vehicle page
When complaints were filed
Does it get worse with age? Complaints per calendar year filed
1
1
0
1
1
1
1
View as table
| Model year | Complaints filed per calendar year |
|---|---|
| 2018 | 1 |
| 2019 | 1 |
| 2020 | 0 |
| 2021 | 1 |
| 2022 | 1 |
| 2023 | 1 |
| 2024 | 1 |
Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.
Top problems in owners’ words
Verbatim from NHTSA complaints, newest first
Engine
5 reports
“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 NHTSA Campaign Number: 22V178000 (Engine and Engine Cooling). The manufacturer had been informed of the failure. The failure mileage was approximately 116,000.”
Power train
1 report
“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”
Data from NHTSA Complaints API (owner reports, unverified) · synced Oct 29, 2026
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.