Line Pressure Test: Measurement

NOTE: If the clutch or brake shows a sign of slippage, or shifting interval is not correct, the line pressure should be checked.

Excessive shocks during up-shift or shifting takes place at a higher point than under normal circumstances, 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.

Set the vehicle on a lift.
Remove the under cover.
Remove the test plug and install the ST.
ST 498897200 OIL PRESSURE ADAPTER

Fig 1: Identifying Oil Pressure Adapter ST 498897200
Courtesy of SUBARU OF AMERICA, INC.
Set the ST1 and ST2.
ST1 498897200 OIL PRESSURE ADAPTER

ST2 498575400 OIL PRESSURE GAUGE ASSY
Lower the vehicle, and pull the ST1 and ST2 into vehicle.
ST1 498897200 OIL PRESSURE ADAPTER

ST2 498575400 OIL PRESSURE GAUGE ASSY
Connect the Subaru Select Monitor to data link connector and read the current data. < Ref. to , READ CURRENT DATA , OPERATION, Subaru Select Monitor. >
1. Start the engine.
2. Turn the Subaru Select Monitor switch to ON.
3. On the << Main Menu>> display screen, select the {Each System Check} and press the [YES] key.
4. On the << System Selection Menu>> display screen, select the {Transmission} and press the [YES] key.
5. Press the [YES] key after the information of transmission type has been displayed.
6. On the << transmission Diagnosis>> display screen, select the {Current Data Display/Save}, and then press the [YES] key.
7. On the << Transmission Diagnosis>> display screen, select the {Data Display} and press the [YES] key.
8. Using the scroll key, display the "P/L solenoid target oil pressure".
Perform the line pressure test.

NOTE:

Do not perform the line pressure test for more than 5 seconds at a time. It makes engine oil and ATF deteriorate and the clutch and brake to be adversely affected.
Be sure to cool down the engine for at least one minute with the select lever set in "P" or "N" range and with the idle speed lower than 1,200 rpm after performing line pressure test.
Adjust the throttle valve angle in order to obtain the "P/L solenoid target pressure" displayed on the Subaru Select Monitor.

P/L SOLENOID TARGET PRESSURE AND STANDARD LINE PRESSURE SPECIFICATION

Range of the selector lever	Throttle valve angle	ATF temperature condition	"P/L Solenoid Target Pressure" displayed on the Subaru Select Monitor kPa	Standard line pressure kPa (kg/cm² , psi)
D	Full closed	45 - 55°C (104-131 °F)	490	385-555 (3.93-5.66, 55.8-80.5)
D	Full open		1,370	1,235-1,475 (12.59-15.04, 179.1-213.9)
R	Full closed		1,370	1,530-1,925 (15.60-19.6, 221.9-279.2)