This bulletin applies to 2014-2018 Subaru Forester Turbo and 2015-2019 WRX vehicles. A design change was made to the TGV (tumble generator valve) assemblies.
The TGVs are butterfly valves that kick in during cold startup and should open fully once operating temperature is achieved.
Condensation resulting from the EGR system operation may enter the area between the TGV shaft and bearing. Over time, corrosion can develop and impede movement of the TGV shaft and may cause DTC P2004, P2005, P2006 and/or P2007 to set.
The material of the TGV shaft has been changed to stainless steel to optimize corrosion resistance. The new TGVs were incorporated into WRX production starting with VIN K9817040.
The new intake control assemblies featuring the new design TGVs are available as follows:
Right side.............. 14111AA041