Subaru Impreza 2002 Service Manual page 3012

2) Stop the engine and watch vacuum gauge.
If the vacuum drop range is less than 3.3 kPa (25
mmHg, 0.98 inHg) within 15 seconds after stopping
engine, the brake booster is functioning properly.
If defective, refer to "AIR TIGHTNESS CHECK".
<Ref. to BR-51, INSPECTION, Brake Booster.>
• Lack of boosting action check
Turn off the engine, and set the vacuum gauge
reading at "0". Then, check the fluid pressure when
brake pedal is depressed. The pressure must be
greater than the standard value listed.
Brake pedal 147 N
force (15 kgf, 33 lb)
686 kPa
2
(7 kg/cm , 100 psi)
14"
Fluid
[ 588 kPa
pres-
2
(6 kg/cm , 85 psi) ]
sure
15" 588 kPa
2
16" (6 kg/cm
[ ]: ABS equipped vehicle.
• Boosting action check
Set the vacuum gauge reading at 66.7 kPa (500
mmHg, 19.69 inHg) by running engine. Then,
check the fluid pressure when brake pedal is de-
pressed. The pressure must be greater than the
standard value listed.
Brake pedal 147 N
force (15 kgf, 33 lb)
5,982 kPa
14"
2
(61 kg/cm
Fluid
pres- 5,296 kPa
sure
15"
(54 kg/cm
768 psi)
4,707 kPa
16"
2
(48 kg/cm
[ ]: ABS equipped vehicle.
BRAKE BOOSTER
294 N
(30 kgf, 66 lb)
1,961 kPa
2
(20 kg/cm , 284 psi)
[ 1,667 kPa
2
(17 kg/cm , 242 psi) ]
1,471 kPa
2
, 85 psi) (15 kg/cm , 213 psi)
294 N
(30 kgf, 66 lb)
7,649 kPa
2
(78 kg/cm , 1,109 psi)
[8,434 kPa (86 kg/
, 868 psi)
2
cm , 1,223 psi)
2
,
9,120 kPa
2
(93 kg/cm , 1,323 psi)
, 683psi)
BR-53
BRAKE