Inspection Before Removal

Air Tight 

1. With a handy vacuum pump, apply vacuum pressure of -66.7 kPa (-500 mmHg, -19.70 inHg) to the brake booster.
2. If the air tight condition cannot be maintained, perform the following operation.
   1. Check the no dirt and dust are present on the brake booster and brake master cylinder matching faces. Clean it if necessary.
   2. Check O-ring on the master cylinder. If anything is found, replace the O-ring. Refer to Removal and Installation .
   3. Check the air tight condition again. If the condition still cannot be maintained, replace the brake booster.