Audi A4 2009–2012 — technical service bulletin
Bulletin A211418 2031245- · NHTSA communication 10122417 · issued Jun 6, 2014
Technical service bulletin
communication type
Engine and Engine Cooling
component
2009–2012
model years
14
vehicle entries
Official summary
Supersedes Technical Service Bulletin Group 21 number 13-16 dated July 9, 2013. The MIL is on. DTC P029900 (Negative Pressure Deviation) is stored as a static fault in the engine control module (ECM), J623 (address word 01). Under certain driving conditions, the linkage for the waste gate actuation can encounter excessive wear which leads to play at the waste gate flap. This leads to boost escaping through a loose flap, which sets DTC P029900 (Negative Pressure Deviation).
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.