Air Tightness Inspection

Start engine.
Stop engine after running it for 2 minutes.
Depress brake pedal several times with the same load as in ordinary braking and observe pedal travel.
If pedal goes down deep the first time but its travel decreases as it is depressed the second time and after, air tightness is obtained.

Fig 1: Depressing Brake Pedal
Courtesy of SUZUKI OF AMERICA CORP.
If pedal travel does not change, air tightness is not obtained.
If defective, inspect vacuum lines and sealing parts, and replace the faulty part. After this, repeat the entire test.

Fig 2: Inspecting Vacuum Lines
Courtesy of SUZUKI OF AMERICA CORP.