lock LEXUS SC400 1991 Service Repair Manual
[x] Cancel search | Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
Page 1980 of 4087

INSPECTION OF FUEL PUMP ECU
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OFBATTERY
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE SEAT CUSHION AND BACK
3. REMOVE QUARTER TRIM
(a) Disconnect the rear side of the scuff plate by pulling it.
(b) Remove clip A.
(c) Remove the belt hole cover by pulling it.
(d) Remove clip B.
(e) Remove the quarter trim by pulling it.
4. DISCONNECT FUEL PUMP ECU CONNECTOR FI±123
EFI SYSTEM
± Electronic Control System (Fuel Pump ECU)
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Page 1985 of 4087

COMPONENTS FOR REMOVAL AND
INSTALLATION
INSPECTION OF ENGINE & ECT ECU
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OFBATTERY
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. DISCONNECT ENGINE & ECT ECU FROM FLOOR P ANEL
(a) Remove the two clips, and pull out the instrument panel
under cover.
FI±128
EFI SYSTEM
± Electronic Control System (Engine & ECT ECU)
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Page 1999 of 4087

TORQUE SPECIFICATIONS
Part tightenedNVmkgf Vcmft Vlbf
Fuel line Union bolt type
Flare nut type2930022
Fuel pipe X Delivery pipe39400 29
Fuel pump bracket X Fuel tank5.455 48 in.Vlbf
Fuel pump set plate X Fuel tank3.940 35 in. Vlbf
Fuel tank X Body25250 18
Fuel sender gauge X Fuel tank2.930 26 in. Vlbf
Fuel inlet pipe X Fuel tank2.930 26 in. Vlbf
Fuel tank main tube X Fuel tank29300 22
Fuel tank return tube X Fuel tank29300 22
Fuel tank evaporation vent tube X Fuel tank29300 22
Air flow meter X Air cleaner case10100 7
Cold start injector X Air intake chamber7.880 69 in. Vlbf
Cold start injector tube X Cold start injector15150 11
Air intake chamber X Intake manifold18185 13
EGR pipe X Air intake chamber18185 13
EGR pipe X RH cylinder head18185 13
Cold start injector tube X RH Delivery pipe15150 11
Throttle body X Air intake chamber18185 13
Fuel return pipe X Fuel pressure regulator35360 26
Fuel pressure regulator X RH delivery pipe29300 22
Delivery pipe X Intake manifold18185 13
Fuel inlet hose X LH delivery pipe39400 29
for SST33340 24
ISC valve X Air intake chamber18185 13
Cold start injector time switch X Front water by±pass joint34350 25
Water temperature sensor X Front water by±pass joint20200 14
Water inlet housing X Water pump18185 13
EGR gas temperature sensor X EGR valve adaptor20200 14
EGR valve adaptor X Air intake chamber18185 13
EGR valve X EGR valve adaptor18185 13
Knock sensor X Cylinder block44450 33
Intake manifold X Cylinder head18185 13
Main oxygen sensor X Exhaust manifold44450 33
Sub±oxygen sensor X Exhaust manifold4445033
FI±142EFI SYSTEM ± Service Specifications
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Page 2018 of 4087

PRECAUTIONS
1. Before working on the fuel system, disconnect the cablefrom negative (±) terminal of the battery.
HINT: Any diagnostic code retained by the computer will be
erased when the battery terminal is removed. Therefore, if
necessary, read the diagnosis before removing the battery
terminal.
CAUTION: Turn the ignition switch to ºLOCKº. Discon-
nect the cable from the negative (±) terminal of the bat-
tery. Wait at least 20 seconds before proceeding with
work.
2. Do not smoke or work on open flame when working on the fuel system.
3. Keep gasoline away from rubber or leather parts.
INSPECTION PRECAUTIONS
MAINTENANCE PRECAUTIONS
1. CHECK CORRECT ENGINE TUNE±UP (See page EM±8)
2. PRECAUTIONS WHEN CONNECTING GAUGE (a) Use the battery as the power source for the timing light,tachometer, etc.
(b) Connect the test probe of a tachometer to the terminal IG of the check connector.
3. IN EVENT OF ENGINE MISFIRE, FOLLOWING PRECAUTIONS SHOULD BE TAKEN
(a) Check proper connection of battery terminals, etc.
(b) Handle high±tension cords carefully.
(c) After repair work, check that the ignition coil terminalsand all other ignition system lines are reconnected
securely.
(d) When cleaning the engine compartment, be especially careful to protect the electrical system from water.
4. PRECAUTIONS WHEN HANDLING OXYGEN SENSOR (a) Do not allow oxygen sensor to drop or hit against anobject.
(b) Do not allow the sensor to come into contact with water.
±
EFI SYSTEM Precautions, Inspection PrecautionsFI±11
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Page 2020 of 4087

8. Care is required when pulling out and inserting wiring
connectors.
(a) Release the lock and pull out the connector, pulling on the connectors.
(b) Fully insert the connector and check that it is locked.
9. Use SST for inspection or test of the injector or its wiring connector.
SST 09842±30070
±
EFI SYSTEM Inspection PrecautionsFI±13
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Page 2023 of 4087

PRECAUTIONS
1. Before working on the fuel system, disconnect the cablefrom negative (±) terminal of the battery.
HINT: Any diagnostic code retained by the computer will be
erased when the battery terminal is removed. Therefore, if
necessary, read the diagnosis before removing the battery
terminal.
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and negative (±) terminal
cable is disconnected from the battery.
2. Do not smoke or work on open flame when working on the fuel system.
3. Keep gasoline away from rubber or leather parts.
INSPECTION PRECAUTIONS
MAINTENANCE PRECAUTIONS
1. CHECK CORRECT ENGINE TUNE±UP (See page EM±8)
2. PRECAUTIONS WHEN CONNECTING GAUGE (a) Use the battery as the power source for the timing light,tachometer, etc.
(b) Connect the test probe of a tachometer to the terminal IG of the check connector.
3. IN EVENT OF ENGINE MISFIRE, FOLLOWING PRECAUTIONS SHOULD BE TAKEN
(a) Check proper connection of battery terminals, etc.
(b) Handle high±tension cords carefully.
(c) After repair work, check that the ignition coil terminalsand all other ignition system lines are reconnected
securely.
(d) When cleaning the engine compartment, be especially careful to protect the electrical system from water.
4. PRECAUTIONS WHEN HANDLING OXYGEN SENSOR (a) Do not allow oxygen sensor to drop or hit against anobject.
(b) Do not allow the sensor to come into contact with water.
FI±12
± Precautions, Inspection PrecautionsEFI SYSTEM
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Page 2025 of 4087

8. Care is required when pulling out and inserting wiring
connectors.
(a) Release the lock and pull out the connector, pulling on the connectors.
(b) Fully insert the connector and check that it is locked.
9. When inspecting a connector with a volt/ohmmeter. (a) Carefully take out the water±proofing rubber if it is a
water±proof type connector.
(b) Insert the test probe into the connector from wiring side when checking the continuity, amperage or voltage.
(c) Do not apply unnecessary force to the terminal.
(d) After checking, install the water±proofing rubber on the connector securely.
10. Use SST for inspection or test of the injector, cold start injector or its wiring connector.
SST 09842±30055 (A) and 09842±30070 (C)
FI±14
EFI SYSTEM
± Inspection Precautions
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Page 2029 of 4087

If there is no pressure, check the following parts:
wFuses
w EFI main relay
w Fuel pump ECU
w Fuel pump
w Engine (& ECT) ECU
w Wiring connections
2. CHECK FUEL PRESSURE (a) Check the battery voltage above 12 volts.
(b) Disconnect the cable from the negative (±) terminal ofthe battery.
CAUTION: Turn the ignition switch to ºLOCKº. Discon-
nect the cable from the negative (±) terminal of the bat-
tery. Wait at least 20 seconds before proceeding with
work.
(c) Remove the union bolt holding the deliver pipe to the No. 1 fuel pipe. Remove the two gaskets.
HINT:
w Put a suitable container or shop towel under the delivery
pipe.
w Slowly loosen the union bolt.
(d) Install the No. 1 fuel pipe and SST (pressure gauge) to the delivery pipe with three new gaskets and the union
bolt.
SST 09268±45012
Torque: 42 N Vm (420 kgf Vcm, 30 ft Vlbf)
(e) Wipe off any splattered gasoline.
(f) Using SST, connect terminals +B and FP of the check
(ºDIAGNOSISº) connector.
SST 09843±18020
(g) Reconnect the cable to the negative (±) terminal of the battery.
±
EFI SYSTEM Fuel System (Fuel Pump)FI±17
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Page 2032 of 4087

REMOVAL OF FUEL PUMP
(See Components on page FI±19)
CAUTION: Do not smoke or work near an open flame
when working on the fuel pump.
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OF BATTERY
CAUTION: Turn the ignition switch to ºLOCKº. Discon-
nect the cable from the negative (±) terminal of the bat-
tery. Wait at least 20 seconds before proceeding with
work.
2. REMOVE LUGGAGE COMPARTMENT FLOOR MAT
3. REMOVE SPARE TIRE
4. REMOVE LUGGAGE COMPARTMENT TRIM COVER
5. DISCONNECT FUEL PUMP CONNECTOR
6. REMOVE SEAT CUSHION AND BACK
7. REMOVE PARTITION COVER Using a scraper, pry out the partition cover.
8. REMOVE FUEL PUMP (a) Remove the eight bolts, and disconnect the fuel pump
set plate from the fuel tank.
(b) Remove the three nuts, and disconnect the fuel pump bracket from the fuel tank.
(c) Disconnect the fuel hose from the fuel pump bracket, and remove the fuel pump, bracket and set plate
assembly.
FI±20
±
EFI SYSTEM Fuel System (Fuel Pump)
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Page 2037 of 4087

If there is no pressure, check the following parts:w Fuses
w EFI main relay
w Fuel pump ECU
w Fuel pump
w Engine & ECT ECU
w Wiring connections
2. CHECK FUEL PRESSURE (a) Check the battery voltage above 12 volts.
(b) Disconnect the cable from the negative (±) terminal ofthe battery.
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and negative (±) terminal
cable is disconnected from the battery.
(c) (Exc. USA Spec.) Remove the filter from the VSV (for EGR system).
(d) Remove the union bolt holding the LH deliver pipe to the
rear fuel pipe. Remove the two gaskets.
HINT:
w Put a suitable container or shop towel under the cold
start injector pipe.
w Slowly loosen the union bolt.
(e) Install the rear fuel pipe and SST (pressure gauge) to the LH delivery pipe with three new gaskets and the
union bolt.
SST 09268±45012
Torque: 39 N Vm (400 kgf Vcm, 29 ft Vlbf)
(f) Wipe off any splattered gasoline.
(g) (Exc. USA Spec.)
Reinstall the filter to the VSV.
(h) Using SST, connect terminals B and FP of the check (ºDIAGNOSISº) connector.
SST 09843±18020
(i) Reconnect the cable to the negative (±) terminal of the
battery.
FI±18
EFI SYSTEM
± Fuel System (Fuel Pump)
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