LEXUS SC400 1991 Service Repair Manual

INSPECTION OF FUEL PUMP
1. INSPECT FUEL PUMP RESISTANCEUsing an ohmmeter, measure the resistance between the ter-
minals.
Resistance: 0.2±3.0

If the resistance is not as specified, replace the fuel pump
and/or set plate.
2. INSPECT FUEL PUMP OPERATION Connect the positive (+) lead from the battery to terminal 1 of
the connector, and the negative (±) lead to terminal 2. Check
that the fuel pump operates.
NOTICE:
w These tests must be performed quickly (within 10
seconds) to prevent the coil from burning out.
w Keep the fuel pump as far away from the battery as
possible.
w Always perform switching at the battery side.
If operation is not as specified, replace the fuel pump and/or
set plate.
COMPONENTS FOR DISASSEMBLY AND
ASSEMBLY
FI±22EFI SYSTEM ± Fuel System (Fuel Pump)
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DISASSEMBLY OF FUEL PUMP
(See Components on page FI±22)
1. REMOVE PUMP SET PLATE FROM FUEL PUMP Disconnect the lead connector from the fuel pump, and re-
move the set plate.
2. REMOVE FUEL PUMP FROM PUMP BRACKET (a) Pull out the lower side of the fuel pump from the pumpbracket.
(b) Remove the rubber cushion from the fuel pump.
(c) Disc onnect the fuel hose from the fuel pump, and
remove the fuel pump.
3. REMOVE FUEL PUMP FILTER FROM FUEL PUMP (a) Using a small screwdriver, remove the clip.
(b) Pull out the pump filter.
ASSEMBLY OF FUEL PUMP
(See Components on page FI±22)
1. INSTALL FUEL PUMP FILTER TO FUEL PUMP Install the pump filter with a new clip.
2. INSTALL FUEL PUMP TO FUEL PUMP BRACKET (a) Connect the fuel hose to the outlet port of the fuel pump.
(b) Install the rubber cushion to the fuel pump.
(c) Install the fuel pump by pushing the lower side of the fuel
pump.
3. INSTALL PUMP SET PLATE TO FUEL PUMP Connect the lead connector on the set plate to the fuel pump.FI±23
EFI SYSTEM
± Fuel System (Fuel Pump)
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INSTALLATION OF FUEL PUMP
(See Components on page FI±20)
1. INSTALL FUEL PUMP (a) Install a new gasket to the pump set plate.
(b) Connect the fuel hose to the fuel pump bracket, andinstall the fuel pump and bracket assembly with the
three nuts.
Torque: 5.4 N Vm (55 kgf Vcm, 48 in. Vlbf)
(b) Install the fuel pump set plate with the eight bolts.
Torque: 3.9 N Vm (40 kgf Vcm, 35 in. Vlbf)
2. INSTALL PARTITION COVER
Install the partition cover with butyl tape.
3. INSTALL SEAT BACK AND CUSHION
4. CONNECT FUEL PUMP CONNECTOR
5. INSTALL LUGGAGE COMPARTMENT TRIM COVER
6. INSTALL SPARE TIRE
7. INSTALL LUGGAGE COMPARTMENT FLOOR MAT
8. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
9. START ENGINE, AND CHECK FOR FUEL LEAKS
FI±24
EFI SYSTEM
± Fuel System (Fuel Pump)
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Fuel Pressure Regulator
ON±VEHICLE INSPECTION
CHECK FUEL PRESSURE (See page FI±17)
COMPONENTS FOR REMOVAL AND
INSTALLATION
REMOVAL OF FUEL PRESSURE
REGULATOR
1. DISCONNECT VACUUM SENSING HOSE FROM FUEL
PRESSURE REGULATOR
2. DISCONNECT NO. 2 FUEL PIPE FROM FUEL PRESSURE
REGULATOR
Remove the union bolt and two gasket, and disconnect the
fuel pipe from the pressure regulator.
HINT:
w Put a suitable container or shop towel under the
pressure regulator.
w Slowly loosen the union bolt.
3. REMOVE FUEL PRESSURE REGULATOR (a) Remove the two bolts and pressure regulator.
(b) Remove the O±ring from the pressure regulator.
FI±24
±
EFI SYSTEM Fuel System (Fuel Pressure Regulator)
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INSTALLATION OF FUEL PRESSURE
REGULATOR
(See components on page FI±24)
1. INSTALL FUEL PRESSURE REGULATOR AND FUEL RETURN PIPE
(a) Apply a light coat of gasoline to a new O±ring, and install
it to the pressure regulator.
(b) Install the pressure regulator with the two bolts.
Torque: 8.8 N Vm (90 kgf Vcm, 78 in. Vlbf)
2. CONNECT NO. 2 FUEL PIPE TO FUEL PRESSURE
REGULATOR
Connect the fuel pipe to the pressure regulator with new two
gaskets and the union bolt.
Torque: 27 N Vm (280 kgf Vcm, 20 ft Vlbf)
3. CONNECT VACUUM SENSING HOSE TO FUEL
PRESSURE REGULATOR
4. CHECK FOR FUEL LEAKS (See page FI±15)
±
EFI SYSTEM Fuel System (Fuel Pressure Regulator)FI±25
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Cold Start Injector
FI±25 ± Fuel System (Cold Start Injector)EFI SYSTEM
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COMPONENTS FOR REMOVAL AND INSTALLATION
FI±26EFI SYSTEM ± Fuel System (Cold Start Injector)
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REMOVAL OF COLD START INJECTOR
(See Components on page FI±26)
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OF 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 the negative (±) termi-
nal cable is disconnected from the battery.
2. DRAIN ENGINE COOLANT (See page CO±6)
3. REMOVE THROTTLE BODY COVER (a) Remove the mounting cap nut.
(b) Loosen the two bolts, and remove the throttle bodycover.
4. DISCONNECT CONTROL CABLES FROM THROTTLE BODY
Disconnect the following cables:(1) Accelerator cable
(2) A/T throttle control cable
(3) (w/ Cruise Control System)
Cruise control actuator cable
5. REMOVE INTAKE AIR CONNECTOR (a) Disconnect the following hoses:(1) Air hose from ISC valve
(2) Air hose (from PS air control valve) from intake air connector
(b) Remove the bolt holding the intake air connector to the cylinder head cover.
(c) Loosen the two hose clamps.
(d) Disconnect the intake air connector from the throttle body and air cleaner hose, and remove the intake air
connector. FI±27
EFI SYSTEM
± Fuel System (Cold Start Injector)
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6. REMOVE UPPER HIGH±TENSION CORD COVER(a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord coverfrom the claw of the lower cover, and remove the cord
cover.
7. REMOVE RH ENGINE WIRE COVER Remove the bolt and wire cover.
8. REMOVE LH ENGINE WIRE COVER Remove the two bolts and wire cover.
9. REMOVE VSV FOR EVAP SYSTEM Remove the two bolts, and disconnect the VSV from cylinder
head and timing belt cover.
10. REMOVE RH NO.3 TIMING BELT COVER Remove the three bolts and timing belt cover.
FI±28
EFI SYSTEM
± Fuel System (Cold Start Injector)
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11. REMOVE LH NO.3 TIMING BELT COVER(a) Remove the four mounting bolts.
(b) Disconnect the cord grommet from the timing belt cover,
and remove the timing belt cover.
(c) Remove the cord grommet from the high±tension cord.
12. REMOVE LOWER HIGH±TENSION CORD COVER (a) Disconnect the high±tension cord from the RH ignitioncoil.
(b) D i s c onnect the high±tension cords from the
high±tension cord cover.
(c) Remove the bolt and cord cover.
13. REMOVE THROTTLE BODY (a) Disconnect the following connectors:(1) Throttle position sensor connector
(2) (w/ TRAC) Sub±throttle position sensor connector
(3) (w/ TRAC) Sub±throttle actuator connector
(b) Disconnect the following hoses: (1) Heater water hose from heater water valve FI±29
EFI SYSTEM
± Fuel System (Cold Start Injector)
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