Brake Booster: Inspection

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT VACUUM CHECK VALVE
1. Inspect the vacuum check valve.
  1. Remove the vacuum check valve.
  2. Check that there is ventilation from the booster to the engine, and no ventilation from the engine to the booster.
  HINT
  
  If any fault is found, replace the vacuum check valve
  
  Fig 1: Checking Ventilation
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