Dodge RAM TRUCK 1500 1995 Service Manual page 180

5 - 8 SERVICE BRAKE DIAGNOSIS
B R
SHORT
CONNECTING
HOSE
CHECK
VALVE
TEE
FITTING
CHECK
VALVE
HOSE
INTAKE
MANIFOLD
VACUUM
GAUGE
(3) Run engine at curb idle speed and note vacuum
reading. Then run engine at 1/2 to 3/4 throttle and
note vacuum reading again.
(4) Vacuum should range from 8.5 to 25 inches vac­
uum at various throttle openings. Vacuum should
hold steady and not drop below 8.5 inches.
(5) If vacuum output is OK, check booster and
check valve as described in this section. However, if
vacuum is low, or does not hold steady, vacuum hoses
and/or pump are faulty.
J9005-81
Fig. 3 Booster Vacuum Test Connections
(2) Disconnect vacuum hose at booster and connect
vacuum gauge to hose end.