Line Pressure Test - Subaru 2002 IMPREZA Service Manual

AUTOMATIC TRANSMISSION

7. Line Pressure Test

A: MEASUREMENT
1. GENERAL INFORMATION
If the clutch or the brake shows a sign of slippage or
shifting sensation is not correct, the line pressure
should be checked.
• Excessive shocks during upshifting or shifting
takes place at a higher point than under normal cir-
cumstances, may be due to the line pressure being
too high.
• Slippage or inability to operate the vehicle may,
in most cases, be due to loss of oil pressure for the
operation of the clutch, brake or control valve.
1) Line pressure measurement (under no load)
NOTE:
• Before measuring the line pressure, jack-up all
wheels.
• Maintain the temperature of ATF at approx. 50°C
(122°F) during measurement.
(ATF will reach the above temperature after idling
the engine for approx. 30 minutes with select lever
in "N" or "P".)
2) Line pressure measurement (under heavy load)
NOTE:
• Before measuring the line pressure, apply both
foot and parking brakes with all wheels chocked
(Same as for "stall" test conditions).
• Measure the line pressure when select lever is in
"R", "2" with engine under stall conditions.
• Measure the line pressure within 5 seconds after
shifting the select lever to each position. (If line
pressure needs to be measured again, allow the
engine to idle and then stop. Wait for at least 1
minute before measurement.)
• Maintain the temperature of ATF at approx. 50°C
(122°F) during measurement (ATF will reach the
above temperature after idling the engine for ap-
prox. 30 minutes with the select lever in "N" or "P".)
LINE PRESSURE TEST
2. TEST METHODS
1) Temporarily attach the ST to a suitable place in
the driver's compartment, remove the blind plug lo-
cated in front of the toe board and pass the hose of
the ST to engine compartment.
ST 498575400
2) Remove the test plug and install the ST instead.
ST 498897200
3) Connect the ST1 with ST2.
ST1 498897200
ST2 498575400
AT-16
OIL PRESSURE GAUGE
ASSY
(A) Pressure gauge hose
(B) Hole in toe board (blank cap hole)
(C) Brake pedal
OIL PRESSURE GAUGE
ADAPTER
(A) Test plug
OIL PRESSURE GAUGE
ADAPTER
OIL PRESSURE GAUGE
ASSY
B3M0568C
B3M2264A