1997 SUBARU LEGACY check engine

C: LINE PRESSURE TEST
1. GENERAL
If the clutch or the brake band 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 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 band or control valve.
G3M0869
1) Line pressure measurement (under no load)
CAUTION:
Before measuring line pressure, jack-up front
wheels (front-wheel-drive model) or all wheels (4-wheel
drive model).
Maintain temperature of ATF at approximately 50°C
(122°F) during measurement.
(ATF will reach the above temperature after idling the
engine for approximately 30 minutes with select lever
in“N”or“P”.)
G3M0869
2) Line pressure measurement (under heavy load)
CAUTION:
Before measuring line pressure, apply both foot and
parking brakes with all wheels chocked (Same as for
“stall”test conditions).
Measure line pressure when select lever is in“R”,
“2”with engine under stall conditions.
Measure line pressure within 5 seconds after shift-
ing 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 one minute before mea-
surement.)
Maintain the temperature of ATF at approximately
50°C (122°F) during measurement. (ATF will reach the
above temperature after idling the engine for approxi-
mately 30 minutes with the select lever in“N”or“P”.)
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3-2SERVICE PROCEDURE
3. Performance Test

G3M0317
2. TEST METHODS
1) Temporarily attach the ST to a suitable place in the
driver’s compartment, remove the blind plug located in
front of the toe board and pass the hose of the ST to the
engine compartment.
ST 498575400 OIL PRESSURE GAUGE ASSY


1Pressure gauge hose


2Hole in toe board (blank cap hole)


3Brake pedal
G3M0869
2) Remove the test plug and install ST1 instead.
3) Connect ST1 with ST2.
ST1 498897200 OIL PRESSURE GAUGE ADAPTER
ST2 498575400 OIL PRESSURE GAUGE ASSY
4) Check for duty ratio changes by opening and closing
throttle valve using select monitor.
5) Check line pressure in accordance with the following
chart.
3. EVALUATION
NOTE:
Under no load:“D”
Under full load:“R”,“2”
(With engine running at stall speed)

Unit: kPa (kg/cm2, psi)
Line pressure
Duty ratio (%)“2”range“R”range“D”range
2200 cc 2500 cc
51,147—1,344
(11.7—13.1, 166—195)1,275—1,569
(13.0—16.0, 185—228)—
22——765—902
(7.8—9.2, 111—131)
100——235—481
(2.4—4.9, 34—70)392—490
(4.0—5.0, 57—71)
42
3-2SERVICE PROCEDURE
3. Performance Test

G3M0870
D: TRANSFER CLUTCH PRESSURE TEST
Check transfer clutch pressure in accordance with the fol-
lowing chart in the same manner as with line pressure.
ST 499897700 OIL PRESSURE ADAPTER SET
ST 498575400 OIL PRESSURE GAUGE ASSY
AWD mode:“D”range
FWD mode:“P”range, engine speed 2000 rpm
CAUTION:
Before setting in FWD mode, install spare fuse on FWD
mode switch.
Unit: kPa (kg/cm2, psi)
Duty ratio
(%)AWD mode FWD mode
5667—804
(6.8—8.2, 97—117)667—804
(6.8—8.2, 97—117)
40137—226
(1.4—2.3, 20—33)—
950
(0, 0)—
If oil pressure is not produced or if it does not change in the
AWD mode, the duty solenoid C or transfer valve assem-
bly may be malfunctioning. If oil pressure is produced in the
FWD mode, the problem is similar to that in the AWD
mode.
E: ROAD TEST
1. GENERAL
Road tests should be conducted to properly diagnose the
condition of the automatic transmission.
CAUTION:
When performing test, do not exceed posted speed
limit.
2. CHECKING FOR SHIFT PATTERNS
Check“kick-down”.
D range: 1st
←
→2nd←
→3rd←
→4th
3 range: 1st←
→2nd←
→3rd←4th
2 range: 2nd←3rd←4th
1 range: 1st←2nd←3rd←4th
3. CHECK FOR ENGINE BRAKE OPERATION
Engine brake operation:
D range→4th gear
3 range→3rd gear
2 range→2nd gear
1 range→1st gear
43
3-2SERVICE PROCEDURE
3. Performance Test

10) After completion of fitting, make sure that the selector
lever operates smoothly all across the operating range.
11) Connect the harnesses and check the following items.
(1) The engine starts operating when selector lever is
in position“P”, but not in other positions.
(2) The back-up light is lit when the selector lever is in
position“R”, but not in other positions.
B3M0348A
12) Check selector lever operation.
WARNING:
Stop the engine while checking operation of selector
lever.
(1) Check that selector lever does not move from“N”
to“R”without pushing the button.
(2) Check that selector lever does not move from“R”
to“P”without pushing the button.
(3) Check that selector lever does not move from“P”
to“R”without pushing the button and the brake pedal
depressed. [With ignition key set at“ON”.]
(4) Check that selector lever does not move from“3”to
“2”without pushing the button.
13) Check shift-lock system.
(1) Ensure ignition switch rotates from“ACC”to
“LOCK”when the selector lever is set at“P”. Also check
that ignition key can be removed from the“LOCK”posi-
tion only.
(2) Ensure selector lever moves from“P”to any other
position when the brake pedal is depressed with igni-
tion key set at“ON”or“START”.
16
3-3SERVICE PROCEDURE
2. Automatic Transmission

Symptom and possible cause Remedy
5. Noises when cornering


1Damaged differential gear. Replace.


2Excessive wear or damage of thrust washer. Replace.


3Broken pinion mate shaft. Replace.


4Seized or damaged side bearing. Replace.
6. Gear noises
Since noises from engine, muffler, transmission, propeller shaft, wheel bearings, tires, and body are sometimes mistaken for noises
from differential assembly, be careful in checking them. Inspection methods to locate noises include coasting, accelerating, cruising,
and jacking-up all four wheels. Perform these inspections according to condition of trouble. When listening to noises, shift gears into
four wheel drive and fourth speed position, trying to pick up only differential noise.


1Improper tooth contact of hypoid gear. Readjust or replace hypoid gear set.


2Improper backlash for hypoid gear. Readjust.


3Scored or chipped teeth of hypoid gear. Replace hypoid gear set.


4Seized hypoid gear. Replace hypoid gear set.


5Improper preload for front or rear bearings. Readjust.


6Seized, scored, or chipped front or rear bearing. Replace.


7Seized, scored, or chipped side bearing. Replace.


8Vibrating differential carrier. Replace.
2. Propeller Shaft
Symptom and possible cause Remedy
1. Vibration of propeller shaft
Vibration is caused by propeller shaft during operation and is transferred to vehicle body. Generally vibration increase in proportion to
vehicle speed.


1Worn or damaged universal joint. Replace.


2Unbalanced propeller shaft due to bend or dent. Replace.


3Loose installation of propeller shaft. Retighten.


4Worn or damaged center bearing and damaged center mount-
ing rubber.Replace.
2. Tapping when starting and noise while cruising, caused by propeller shaft.


1Worn or damaged universal joint. Replace.


2Worn spline of sleeve yoke. Replace.


3Loose installation of propeller shaft. Retighten.


4Loose installation of joint. Replace.


5Worn or damaged center bearing and damaged center mount-
ing rubber.Replace.
NOTE:
Vibration while cruising may be caused by an unbalanced
tire, improper tire inflation pressure, improper wheel
alignment, etc.
41
3-4DIAGNOSTICS
1. Rear Differential - 2. Propeller Shaft

Symptom and possible cause Remedy
5. Noises when cornering


1Damaged differential gear. Replace.


2Excessive wear or damage of thrust washer. Replace.


3Broken pinion mate shaft. Replace.


4Seized or damaged side bearing. Replace.
6. Gear noises
Since noises from engine, muffler, transmission, propeller shaft, wheel bearings, tires, and body are sometimes mistaken for noises
from differential assembly, be careful in checking them. Inspection methods to locate noises include coasting, accelerating, cruising,
and jacking-up all four wheels. Perform these inspections according to condition of trouble. When listening to noises, shift gears into
four wheel drive and fourth speed position, trying to pick up only differential noise.


1Improper tooth contact of hypoid gear. Readjust or replace hypoid gear set.


2Improper backlash for hypoid gear. Readjust.


3Scored or chipped teeth of hypoid gear. Replace hypoid gear set.


4Seized hypoid gear. Replace hypoid gear set.


5Improper preload for front or rear bearings. Readjust.


6Seized, scored, or chipped front or rear bearing. Replace.


7Seized, scored, or chipped side bearing. Replace.


8Vibrating differential carrier. Replace.
2. Propeller Shaft
Symptom and possible cause Remedy
1. Vibration of propeller shaft
Vibration is caused by propeller shaft during operation and is transferred to vehicle body. Generally vibration increase in proportion to
vehicle speed.


1Worn or damaged universal joint. Replace.


2Unbalanced propeller shaft due to bend or dent. Replace.


3Loose installation of propeller shaft. Retighten.


4Worn or damaged center bearing and damaged center mount-
ing rubber.Replace.
2. Tapping when starting and noise while cruising, caused by propeller shaft.


1Worn or damaged universal joint. Replace.


2Worn spline of sleeve yoke. Replace.


3Loose installation of propeller shaft. Retighten.


4Loose installation of joint. Replace.


5Worn or damaged center bearing and damaged center mount-
ing rubber.Replace.
NOTE:
Vibration while cruising may be caused by an unbalanced
tire, improper tire inflation pressure, improper wheel
alignment, etc.
41
3-4DIAGNOSTICS
1. Rear Differential - 2. Propeller Shaft

G4M0520
6. Front Crossmember
A: REMOVAL
1) Disconnect ground cable from battery.
2) Loosen front wheel nuts.
3) Lift-up vehicle, and remove front tires and wheels.
4) Remove both stabilizer and jack-up plate.
5) Disconnect tie-rod end from housing.
6) Remove front exhaust pipe.
G4M0521
7) Remove front transverse link from front crossmember
and body.
8) Remove nuts attaching engine mount cushion rubber to
crossmember.
9) Remove self-locking nuts connecting steering U/J and
pinion shaft.
10) Lift engine by approx. 10 mm (0.39 in) by using chain
block.
11) Support crossmember with a jack, remove nuts secur-
ing crossmember to body and lower crossmember gradu-
ally along with steering gearbox.
CAUTION:
When removing crossmember downward, be careful
that tie-rod end does not interfere with DOJ boot.
B: INSTALLATION
1) Installation is in the reverse order of removal proce-
dures.
CAUTION:
Always tighten rubber bushing when wheels are in full
contact with the ground and vehicle is at curb weight
condition.
Tightening torque:
Transverse link bushing to crossmember:
98±15 N⋅m (10.0±1.5 kg-m, 72±11 ft-lb)
Stabilizer to bushing:
25±4 N⋅m (2.5±0.4 kg-m, 18.1±2.9 ft-lb)
Tie-rod end to housing:
27.0±2.5 N⋅m (2.75±0.25 kg-m, 19.9±1.8 ft-lb)
Front cushion rubber to crossmember:
69±15 N⋅m (7.0±1.5 kg-m, 51±11 ft-lb)
Universal joint to pinion shaft:
24±3 N⋅m (2.4±0.3 kg-m, 17.4±2.2 ft-lb)
Crossmember to body:
98±15 N⋅m (10.0±1.5 kg-m, 72±11 ft-lb)
2) Purge air from power steering system.
NOTE:
Check wheel alignment and adjust if necessary.
28
4-1SERVICE PROCEDURE
6. Front Crossmember

5. Control Valve (Power Steering
Gearbox) [LHD model]
NOTE:
This section focuses on the disassembly and reassembly
of control valve. For the inspection and adjustment and the
service procedures for associated parts, refer to“Steering
Gearbox”.
G4M0136
1Power cylinder

2Cylinder

3Rack piston

4Rack axle

5Input shaft
6Torsion bar

7Valve housing

8Valve body

9Control valve
10Pipe B

11Pipe A

12Pinion

13Pinion axle
A: CHECKING OIL LEAKING POINTS
1. OIL LEAKING POINTS
1) If leak point is other than a, b, c, or d, perform check
step 5) in 4-3 [W5A2] before dismounting gearbox from
vehicle. If gearbox is dismounted without confirming where
the leak is, it must be mounted again to locate the leak
point.
2) Even if the location of the leak can be easily found by
observing the leaking condition, it is necessary to thor-
oughly remove the oil from the suspected portion and turn
the steering wheel from lock to lock about 30 to 40 times
with engine running, then make comparison of the sus-
pected portion between immediately after and several
hours after this operation.
3) Before starting oil leak repair work, be sure to clean the
gearbox, hoses, pipes, and surrounding parts. After com-
pleting repair work, clean these areas again.
40
4-3SERVICE PROCEDURE
5. Control Valve (Power Steering Gearbox) [LHD model]