Audi A8 2013–2016 — technical service bulletin
Bulletin A171566 2040644- · NHTSA communication 10130222 · issued Oct 14, 2015
Technical service bulletin
communication type
Engine and Engine Cooling
component
2013–2016
model years
20
vehicle entries
Official summary
Supersedes Technical Service Bulletin Group 17 number 15-64 dated June 3, 2015. A metallic whistling or grinding sound is heard from the engine compartment when the vehicle is at idle speed. The sound usually only occurs when the engine is warm. The MIL is sporadically on. DTCs are stored in the ECM. A leak in the crankcase breather module (pressure regulating valve) can cause this condition.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.