1991 LEXUS SC400 exhaust

ABBREVIATIONS USED IN THIS
MANUAL
ABS Anti±Lock Brake System J/B Junction Block
A/C Air Conditioner LED Light Emitting Diode
ALR Automatic Locking Retractor LH Left±Hand
APPROX. Approximation LHD Left±Hand Drive
A/T, ATM Automatic Transmission LLC Long Life Coolant (Year Around Coolant)
ATF Automatic Transmission Fluid Max. Maximum
BTDC Before Top Dead Center Min. Minimum
BVSV Bimetal Vacuum Switching Valve MP Multipurpose
CALIF. Vehicles Sold in California N Neutral
CB Circuit Breaker OD, O/D Overdrive
DOHC Double Over Head Cam O/S Oversize
DP Dash Pot P & BV Proportioning and Bypass Valve
ECT Electronic Controlled Transmission PCV Positive Crankcase Ventilation
ECU Electronic Controlled Unit PS Power Steering
EFI Electronic Fuel Injection RH Right±Hand
EGR Exhaust Gas Recirculation RL Rear Left
ELR Emergency Locking Retractor RR Rear Right
EPR Evaporator Pressure Regulator RR, Rr Rear
ESA Electronic Spark Advance SRS Supplemental Restraint System
EVAP Evaporative (Emission Control) SSM Special Service Materials
EX Exhaust (manifold, valve) SST Special Service Tools
Ex. Except STD Standard
FIPG Formed in Place Gasket SW Switch
FL Front Left TDC Top Dead Center
FL Fusible Link TDCL Total Diagnostic Communication Link
FPU Fuel Pressure Up Temp. Temperature
FR Front Right TRAC Traction Control System
FR, Fr Front TWC Three±Way Catalyst
HAC High Altitude Compensation VSV Vacuum Switching Valve
IG Ignition VTV Vacuum Transmitting Valve
IN Intake (manifold, valve) w/ With
INT Intermittent w/o Without
ISC Idle Speed Control
IN±34±
INTRODUCTION Abbreviations Used in This Manual
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MEASURE LINE PRESSURE
NOTICE:
Perform the test at normal operating fluid temperature 50±80 C (122±176 F).
 The line pressure test should always be carried out in pairs. One technicia\
n should observe the
conditions of wheels or wheel stoppers outside the vehicle while the other is perf\
orming the test.
 Be careful to prevent the oil pressure gauge hose from interfering with \
the exhaust pipe.
(a) Warm up the transmission fluid.
(b) Remove the test plug on the transmission case left side and connect the \
oil pressure gauge SST.
SST 09992±00094
HINT: Connecting the oil pressure gauge will be made easier by moving LH sid\
e heat insulator aside.
(c) Fully apply the parking brake and chock the 4 wheels.
(d) Start the engine and check idling RPM.
(e) Keep your left foot pressed firmly on the brake pedal and shift into D p\
osition.
(f) Measure the line pressure when the engine is idling.
(g) Press the accelerator pedal all the way down. Quickly read the highest line pressure when engine speedreaches stall speed.
(h) In the same manner, perform the test in R position. AT±54
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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MEASURE ACCUMULATOR BACK PRESSURE
AT0QU±01
NOTICE:
Perform the test at normal operating fluid temperature 50±80 C (122±176 F).
 Be careful to prevent the oil pressure gauge hose from interfering with \
the exhaust pipe.
(a) Warm up the transmission fluid.
(b) Remove the test plug on the transmission case rear right side and connec\
t the oil pressure gauge SST.
SST 09992±00094
HINT: Connecting the oil pressure gauge will be made easier by moving the RH \
side head insulator aside.
(c) Remove the passenger side No.2 under cover and ECM protector.
(d) Connect the SST (check harness A) between ECM and connector of vehicle\
wire harness.
SST: 09990±01000
(e) Install one test lead probe into the terminal SLN of the ECM wire harnes\
s side connector and take care not to ground the other test lead probe.
HINT: Prepare test leads which are connected with an (approximately) 8 W l\
ight bulb.
AT±56
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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ON±VEHICLE REPAIR
AT06Y±04
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the ªLOCKº posi-
tion and the negative (±) terminal cable is disconnected
from the battery.
EXTENSION HOUSING
EXTENSION HOUSING REAR OIL SEAL
REPLACEMENT
AT0QW±01
1. DRAIN ATF
2. REMOVE FRONT EXHAUST PIPE AND HEAT INSULATOR
(See pages EG±204)
3. REMOVE PROPELLER SHAFT (See pages PR±6)
4. REMOVE TRANSMISSION OUTPUT FLANGE
(a) Using a hammer and chisel, loosen the staked part of the nut.
HINT: Shift the shift lever to the P position.
(b) Using SST, remove the nut.
SST 09060±20100
(c) Tap the output flange with a plastic hammer to remove it and 2 washers.
(d) Using a screwdriver, remove the oil seal from the output flange.
5. REMOVE EXTENSION HOUSING REAR OIL SEAL Using SST, remove the oil seal.
SST 09308±00010
AT±14
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION EXTENSION HOUSING
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6. INSTALL EXTENSION HOUSING REAR OIL SEAL
(a) Coat the lip of oil seal with MP grease.
(b) Using SST and a hammer, drive in a new oil seal with the lipfacing downward.
SST 09309±37010
Oil seal depth from flat end:
0±0.3 mm (0±0.012 in.)
7. INSTALL TRANSMISSION OUTPUT FLANGE
(a) Using SST and a hammer, drive in a new oil seal.SST 09517±36010
(b) Install the output flange and 2 washers.
(c) Using SST, install and torque a new nut. SST 09060±20010
Torque: 123 N Vm (1,250 kgf Vcm, 90 ft Vlbf)
HINT: Shift the shift lever to the P position.
(d) Using a hammer and chisel, stake the nut.
8. INSTALL PROPELLER SHAFT (See pages PR±12)
9. INSTALL FRONT EXHAUST PIPE AND HEAT INSULATOR (See page EG±204)
10. FILL WITH ATF
11. CHECK FLUID LEVEL (See page AT±47)
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION EXTENSION HOUSINGAT±15
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NO.2 VEHICLE SPEED SENSOR
REPLACEMENT
AT0GF±02
1. DISCONNECT NO.2 VEHICLE SPEED SENSORCONNECTOR
2. REMOVE NO.2 VEHICLE SPEED SENSOR
(a) Remove the bolt and No.2 vehicle speed sensor.
(b) Remove the O±ring from it.
3. INSPECT NO.2 VEHICLE SPEED SENSOR (See page AT±86)
4. INSTALL NO.2 VEHICLE SPEED SENSOR
(a) Cost a new O±ring with ATF and install it to the speed sensor.
(b) Install the speed sensor and torque the bolt.
Torque: 5.4 N Vm (55 kgf Vcm, 48 in. Vlbf)
5. CONNECT NO.2 VEHICLE SPEED SENSOR
CONNECTOR
O/D DIRECT CLUTCH SPEED SENSOR
REPLACEMENT
AT072±04
1. REMOVE FRONT EXHAUST PIPE AND LH SIDECATALYTIC CONVERTER
(See pages EG±204)
2. REMOVE LH SIDE HEAT INSULATORS
3. DISCONNECT O / D DIRECT CLUTCH SPEED SENSOR CONNECTOR
4. REMOVE O/D DIRECT CLUTCH SPEED SENSOR
(a) Remove the bolt and O/D direct clutch speed sensor.
(b) Remove the O±ring from it.
5. INSPECT O/D DIRECT CLUTCH SPEED SENSOR (See page AT±98)
6. INSTALL O/D DIRECT CLUTCH SPEED SENSOR
(a) Coat a new O±ring with ATF and install it to the O/D direct clutch speed sensor.
(b) Install the O/D direct clutch speed sensor and torque the bolt.
Torque: 5.4 N Vm (55 kgf Vcm, 48 in. Vlbf)
7. CONNECT O/D DIRECT CLUTCH SPEED SENSOR
CONNECTOR
8. INSTALL LH SIDE HEAT INSULATORS
9. INSTALL LH SIDE CATALYTIC CONVERTER AND FRONT EXHAUST PIPE
(See page EG±204)
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION SPEED SENSORAT±17
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PARK/NEUTRAL POSITION (PNP)
SWITCH
PARK/NEUTRAL POSITION SWITCH
REPLACEMENT
AT073±04
1. REMOVE FRONT EXHAUST PIPE(See pages EG±204)
2. DISCONNECT PARK/NEUTRAL POSITION SWITCH CONNECTOR
3. REMOVE PARK/NEUTRAL POSITION SWITCH
(a) Remove the control shaft lever.
(b) Pry off the lock washer and remove the nut.
(c) Remove the bolt and pull out the park/neutral position switch.
4. INSPECT PARK/NEUTRAL POSITION SWITCH
(See page AT±106)
5. INSTALL AND ADJUST PARK/NEUTRAL POSITION SWITCH
(See page AT±49)
6. CONNECT PARK/NEUTRAL POSITION SWITCH
CONNECTOR
7. INSTALL FRONT EXHAUST PIPE (See page EG±204)
KICK±DOWN SWITCH
KICK±DOWN SWITCH REPLACEMENT
AT074±04
1. REMOVAL OF KICK±DOWN SWITCH
(a) Remove the 3 bolts and kick±down switch.
(b) Disconnect the kick±down switch connector.
2. INSTALLATION OF KICK±DOWN SWITCH
(a) Connect the kick±down switch connector.
(b) Install the kick±down switch and 3 bolts.
AT±18
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION KICK±DOWN SWITCH
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VALVE BODY
VALVE BODY REMOVAL
AT0GG±02
1. DRAIN ATF
2. REMOVE FRONT EXHAUST PIPE(See pages EG±204)
3. REMOVE OIL PAN
(a) Remove the 19 bolts.
(b) Install the blade of SST between the transmission case and oil pan, cut off applied sealer.
SST 09032±00100
NOTICE: Be careful not to damage the oil pan flange.
4. EXAMINE PARTICLES IN PANRemove the magnets and use them to collect steel particles.
Carefully look at the foreign matter and particles in the pan
and on the magnets to anticipate the type of wear you will find
in the transmission:
Steel (magnetic) 0 bearing, gear and clutch plate wear
Brass (non±magnetic) 0 bushing wear
5. REMOVE OIL STRAINER Remove the 3 bolts holding the oil strainer to the valve body.
6. REMOVE SOLENOID WIRING
(a) Remove the 2 bolts and the clamp.
(b) Disconnect the 4 connectors from the solenoid valves.
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A304E (1UZ±FE) AUTOMATIC TRANSMISSION VALVE BODYAT±19
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