Subaru Workshop Service and Repair Manuals

Vacuum Brake Booster: Pressure, Vacuum and Temperature Specifications

Without ABS

PRESSURE WITHOUT ENGINE RUNNING: 

Pedal Force: 

147 N (33 lbs.) .................................................................................................................................................................................  785 kPa (114 psi)
294 N (66 lbs.) ..............................................................................................................................................................................  2,158 kPa (313 psi)

PRESSURE WITH ENGINE RUNNING [1]: 

Pedal Force: 

147 N (33 lbs.) ..............................................................................................................................................................................  5,492 kPa (796 psi)
294 N (66 lbs.) ...........................................................................................................................................................................  8,434 kPa (1,223 psi)

[1] Vacuum at 66.7 kPa (19.69 inHg).

With ABS

PRESSURE WITHOUT ENGINE RUNNING: 

Pedal Force: 

147 N (33 lbs.) ...................................................................................................................................................................................  588 kPa (85 psi)
294 N (66 lbs.) ..............................................................................................................................................................................  1,667 kPa (242 psi)

PRESSURE WITH ENGINE RUNNING [1]: 

Pedal Force: 

147 N (33 lbs.) ..............................................................................................................................................................................  5,394 kPa (782 psi)
294 N (66 lbs.) .........................................................................................................................................................................  10,003 kPa (1,450 psi)

[1] Vacuum at 66.7 kPa (19.69 in Hg).