Smoke Under Boost - Incorrect PCV Routing Pressurizing Crankcase

After modifying the PCV system (attempting to route through a catch can using the throttle body as a vacuum source), the engine produced smoke when getting into boost. The boost pressure was being fed back into the crankcase ventilation system instead of vacuum, pressurizing the crankcase.

The PCV system was incorrectly routed using the throttle body port as a vacuum source for a catch can setup. The throttle body port provides vacuum at idle but switches to positive pressure under boost, which pressurized the entire crankcase ventilation system. The throttle body either lacks a check valve or the existing one was not functioning properly.

High confidence — Original poster confirmed this resolved the issue