Problems · NHTSA complaints
2015 Audi S4 problems
Owners filed 1 complaint about the 2015 Audi S4 with NHTSA between Jan 2023 and Jan 2023. The most-cited component is engine (1).
Complaints
1
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
- Engine1
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 Nov 13, 2026NHTSA vehicle page
Top problems in owners’ words
Verbatim from NHTSA complaints, newest first
Engine
1 report
“The R&R valve/oil separator unit failed on my 2015 Audi S4 at approximately 71,000 miles. This unit, when fails, can mix the oil and anti-freeze which can seize the engine. I was able to catch the problem before engine failure. Minneapolis Audi repaired the vehicle this week, 1/10/23. There were NO warning indicators except noise. Various media sources have stated that this is a known engine failure concern between 60-90K miles for this engine. Audi does not recognize this as a safety or warranty concern.”
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 13, 2026
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.