WARNING: This page is about a different car, the 2006 Subaru Outback and 2006 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.
Remove the intake duct from the intercooler.
Remove the air bypass valve from intercooler.
Fig 1: Locating Intake Duct From Intercooler And Air By-Pass Valve From Intercooler