clock LEXUS SC400 1991 Service Manual PDF
[x] Cancel search | Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
Page 1806 of 4087

22. INSTALL DELIVERY PIPES AND INJECTORS(a) Install the grommet and a new O±ring to each injector.
(b) W h i l e t u r n i n g t h e I n j e c t o r c l o c k w i s e a n dcounterclockwise, push it to delivery pipe. Install the
eight injectors.
(c) Position the injector connector outward.
(d) Place the eight insulators and four spacers in positions on the intake manifold.
(e) P l a c e t h e e i g h t i n j e c t o r s a n d t w o d e l i v e r y p i p e s assembly in position on the intake manifold.
(f) Temporarily install the c onnector bracket and four
mounting nuts.
(g) Check that the injectors rotates smoothly.
(h) Position the injector connectors outward.
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ENGINE MECHANICAL Cylinder HeadsEM±105
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Page 1820 of 4087

5. REMOVE AIR CLEANER ASSEMBLY(a) Disconnect the high±tension cord from the ignition coil.
(b) Disconnect the volume air flow meter connector.
(c) Disconnect the following hose:(1) PS air hose from No. 4 timing belt cover
(2) PCV hose from No. 2 cylinder head cover
(d) Loosen the hose clamp holding the air cleaner hose to the throttle body.
(e) Remove the three mounting bolts and air cleaner.
6. REMOVE DRIVE BELT, FAN WITH FLUID COUPLING AND
WATER PUMP PULLEY
(a) Loosen the four nuts holding the fluid coupling to the water pump.
(b) Loosen the drive belt tension by turning the drive belt tensioner clockwise, and remove the drive belt.
(c) Remove the four nuts, fluid coupling and water pump
pulley.
7. REMOVE RADIATOR (a) Disconnect the following hoses:(1) Reservior hose from radiator
(2) Upper radiator hose from water inlet
(3) Lower radiator hose from water outlet
(4) (A/T)Two oil cooler hoses from radiator
Plug the hose ends.
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ENGINE MECHANICAL Cylinder BlockEM±65
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Page 1866 of 4087

(c) Connect the following hoses:(1) Reservior hose to radiator
(2) Upper radiator hose to water inlet
(3) Lower radiator hose to water outlet
(4) (A/T)
Two oil cooler hoses to radiator
16. INS TALL WATE R PUMP PULLE Y, FAN WITH FLUID COUPLING AND DRIVE BELT
(a) Align the matchmarks, and install the water pump pulley
and fan with fluid coupling with the four nuts.
(b) Install the drive belt by turning the drive belt tensioner clockwise.
(c) Stretch the belt tight and tighten the four nuts.
Torque: 16 N Vm (165 kgf Vcm, 12 ft Vlbf)
17. INSTALL AIR CLEANER ASSEMBLY
(a) Connect the air cleaner hose to the throttle body.
(b) Install the air cl eaner case with the three mounting bolts.
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ENGINE MECHANICAL Cylinder BlockEM±111
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Page 1881 of 4087

(e) Reinstall the fuel pressure regulator to the RH deliverypipe.
w Fully loosen the lock nut on the pressure regulator.
w Apply a light coat of gasoline to a new O±ring, and
install it to the pressure regulator.
w Completely insert the pressure regulator into the
delivery pipe by hand.
w Turn the pressure regulator counterclockwise until
the vacuum sensing port faces in the direction
indicated in the illustration.
INSTALLATION OF INJECTORS
(See Components on page FI±49)
1. INSTALL INJECTORS AND DELIVERY PIPE (a) Install the grommet to each injector.
(b) Apply a light coat of gasoline to a new O±ring and install
it to each injector.
(c) W h i l e t u r n i n g t h e i n j e c t o r c l o c k w i s e a n d counterclockwise, push it to the delivery pipes. Install
the eight injectors.
(d) Position the injector connector outward.
(e) Place the eight insulators and four spacers in position on the intake manifold.
FI±54
EFI SYSTEM
± Fuel System (Injectors)
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Page 1913 of 4087

(b) Insert a 0.40 mm (0.016 in.) feeler gauge, between thethrottle stop screw and stop lever.
(c) Connect the test probe of an ohmmeter to the terminals
IDL1 and E2 of the sensor.
(d) Gradually turn the sensor clockwise until the ohmmeter deflects, and secure it with the two set screws.
(e) Recheck the continuity between terminals IDL1 and E2.
Clearance between
lever and stop screwContinuity (IDL1±E2)
0.40 mm (0.016 in.)Continuity
0.65 mm (0.026 in.)No continuity
3. (w/ TRAC) INSPECT SUB±THROTTLE ACTUATOR, SUBTHROTTLE
VALVE AND SUB±THROTTLE POSITION SENSOR
A. Inspect sub±throttle actuator Using an ohmmeter, measure the resistance between the ter-
minals (ACM±A and , BCM±B and B).
Resistance: 0.5±1.0
If the resistance is not as specified, replace the actuator
valve.
B. Inspect sub±throttle actuator Remove the three screws and sub±throttle actuator.
FI±74
EFI SYSTEM
± Air Induction System (Throttle Body)
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(d) Gradually turn the sensor clockwise until the ohmmeterdeflects, and secure it with the two set screws.
(e) Recheck the continuity between terminals IDL2 and E2.
Clearance between
lever and stop screwContinuity (IDL2±E2)
0.30 mm (0.012 in.)Continuity
0.50 mm (0.020 in.)No continuity
E. Reinstall sub±throttle actuator Install the sub±throttle actuator with the three screws.
FI±76
EFI SYSTEM
± Air Induction System (Throttle Body)
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Page 1919 of 4087

11. RECONNECT DRIVER BELTInstall the drive belt by turning the drive belt tensioner clock-
wise.
12. RECONNECT CABLE FROM NEGATIVE TERMINAL OF BATTERY
13. REFILL WITH ENGINE COOLANT
Knock Sensors
INSPECTION OF KNOCK SENSORS
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.
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EFI SYSTEM Electronic Control System (Water Temperature Sensor)FI±69
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Page 2069 of 4087

(e) Install the fuel hose clamp with the two bolts.
INSTALLATION OF INJECTORS
(See Components on page FI±27)
1. INSTALL INJECTORS AND DELIVERY PIPE (a) Install the grommet to each injector.
(b) Apply a light coat of gasoline to a new O±ring and install
it to each injector.
(c) W h i l e t u r n i n g t h e i n j e c t o r c l o c k w i s e a n d counterclockwise, push it to the delivery pipe. Install the
six injectors.
(d) Position the injector connector outward.
(e) Place the six insulators and three spacers in position on
the intake manifold.
(f) Place the six injectors together with the delivery pipe in position on the cylinder head.
FI±32
±
EFI SYSTEM Fuel System (Injectors)
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Page 2082 of 4087

6. DISCONNECT FUEL RETURN PIPE FROM FUELPRESSURE REGULATOR
Remove the union bolt and two gasket, and disconnect the
return pipe from the pressure regulator.
HINT:
wPut a suitable container or shop towel under the
pressure regulator.
w Slowly loosen the union bolt.
7. REMOVE FUEL PRESSURE REGULATOR (a) Loosen the lock nut.
(b) Lift up the water by±pass hose between the ISC valveand throttle body, and remove the pressure regulator.
(c) Remove the O±ring from the pressure regulator.
INSTALLATION OF FUEL PRESSURE
REGULATOR
(See components on page FI±43)
1. INSTALL FUEL PRESSURE REGULATOR AND FUEL RETURN PIPE
(a) Fully loosen the lock nut on the pressure regulator.
(b) Apply a light coat of gasoline to a new O±ring, and install
it to the pressure regulator.
(c) Lift up the water by±pass hose between the ISC valve and throttle body, and completely insert the pressure
regulator into the delivery pipe by hand.
(d) Turn the pressure regulator counterclockwise until the vacuum sensing port faces in the direction indicated in
the illustration. FI±45
EFI SYSTEM
± Fuel System (Fuel Pressure Regulator)
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Page 2125 of 4087

OIL PRESSURE CHECK
1. CHECK ENGINE OIL QUALITYCheck the oil for deterioration, presence of water, discoloring
or thinning.
If the quality is poor, replace the oil.
Oil grade: API grade SG, Energy±Conserving II multigrade.
Recommended viscosity is as shown, with SAE 5W±30 being
the preferred engine oil.
2. CHECK ENGINE OIL LEVELThe oil level should be between the ºLº and ºFº marks on the
dipstick.
If low, check for the leakage and add oil up to ºFº mark.
3. REMOVE ENGINE UNDER COVER
4. REMOVE DRIVE BELT Loosen the drive belt tension by turning the drive belt tension-
er clockwise, and remove the drive belt.
5. DISCONNECT A/C COMPRESSOR WITHOUT DISCONNECTING HOSES
(a) Disconnect the compressor connector.
(b) Remove the four mounting bolts and nut.
(c) R e m o v e t h e t h r ought bolt, and disconnect the
compressor from the engine.
HINT: Put aside the compressor, and suspend it.
6. REMOVE OIL PRESSURE SWITCH, AND INSTALL OIL PRESSURE GAUGE
(a) Disconnect the oil pressure switch connector.
(b) Using SST, remove the oil pressure switch.SST 09816±30010
(c) Install an oil pressure gauge.
±
LUBRICATION SYSTEM Oil pressure CheckLU±5
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