LEXUS SC400 1991 Service Repair Manual

(b) Push the front side of the high±tension cord cover, andconnect the front side claw groove of the upper
high±tension cord cover to the claw of the lower
high±tension cord cover.
(c) Install the upper high±tension cord cover with the two bolts.
13. INSTALL INTAKE AIR CONNECTOR (a) Connect the end portions of the intake air connector tothe throttle body and air cleaner hose.
(b) Tighten the two hose clamps.
(c) Install the bolt holding the intake air connector to the
cylinder head cover.
(d) Connect the following hoses: (1) Air hose to ISC valve
(2) Air hose (from PS air control valve) to intake air con- nector
14. CONNECT CONTROL CABLES TO THROTTLE BODY Connect the following cables:(1) Accelerator cable
(2) A/T throttle control cable
(3) (w/ Cruise Control System) Cruise control actuator cable
15. INSTALL THROTTLE BODY COVER Install the throttle body cover and hose clamp with the two
bolts and cap nut.
16. C O N N E C T C A B L E TO N E G AT I V E T E R M I N A L O F BATTERY
17. FILL WITH ENGINE COOLANT (See page CO±7)
18. CHECK FOR FUEL LEAKS (See page FI±16) FI±41
EFI SYSTEM
± Fuel System (Cold Start Injector)
WhereEverybodyKnowsYourName

Fuel Pressure Regulator
ON±VEHICLE INSPECTION
INSPECT FUEL PRESSURE (See page FI±18)
FI±42
± Fuel System (Fuel Pressure Regulator)EFI SYSTEM
WhereEverybodyKnowsYourName

COMPONENTS FOR REMOVAL AND
INSTALLATION
REMOVAL OF FUEL PRESSURE
REGULATOR
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 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 FI±43
EFI SYSTEM
± Fuel System (Fuel Pressure Regulator)
WhereEverybodyKnowsYourName

(b) Remove the bolt holding the intake air connector to thecylinder 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.
3. REMOVE UPPER HIGH±TENSION CORD COVER (a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord cover
from the claw of the lower cover, and remove the cord
cover.
4. REMOVE RH ENGINE WIRE COVER Remove the bolt and wire cover.
5. DISCONNECT VACUUM SENSING HOSE FROM FUEL PRESSURE REGULATOR
FI±44
EFI SYSTEM
± Fuel System (Fuel Pressure Regulator)
WhereEverybodyKnowsYourName

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)
WhereEverybodyKnowsYourName

(e) Connect the fuel return pipe to the pressure regulatorwith new two gaskets and the union bolt.
Torque: 35 N Vm (360 kgf Vcm, 26 ft Vlbf)
(f) Tighten the lock nut.
Torque: 29 N Vm (300 kgf Vcm, 22 ft Vlb)
2. CONNECT VACUUM SENSING HOSE TO FUEL
PRESSURE REGULATOR
3. INSTALL RH ENGINE WIRE COVER (a) Fit portions A and B of the engine wire cover, matchingthem with the lower high±tension cord cover and No.3
timing belt cover.
(d) Install the engine wire cover with the bolt.
FI±46
EFI SYSTEM
± Fuel System (Fuel Pressure Regulator)
WhereEverybodyKnowsYourName

4. INSTALL UPPER HIGH±TENSION CORD COVER(a) Fit portion A of the upper high±tension cover, matchingit with the top of the lower high±tension cord cover.
(b) Push the front side of the high±tension cord cover, and connect the front side claw groove of the upper
high±tension cord cover to the claw of the lower
high±tension cord cover.
(c) Install the upper high±tension cord cover with the two
bolts.
5. INSTALL INTAKE AIR CONNECTOR (a) Connect the end portions of the intake air connector tothe throttle body and air cleaner hose.
(b) Tighten the two hose clamps.
(c) Install the bolt holding the intake air connector to the
cylinder head cover.
(d) Connect the following hoses: (1) Air hose to ISC valve
(2) Air hose (from PS air control valve) to intake air con-
nector
6. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
7. CHECK FOR FUEL LEAKS (See page FI±16) FI±47
EFI SYSTEM
± Fuel System (Fuel Pressure Regulator)
WhereEverybodyKnowsYourName

Injectors
ON±VEHICLE INSPECTION
INSPECT INJECTOR RESISTANCE(a) Remove the engine wire covers and throttle body.(See steps 1 to 8 and 13 on pages FI±27 to 30)
(b) Disconnect the injector connectors.
(c) Using an ohmmeter, measure the resistance between the terminals.
Resistance: 13.4±14.2

If the resistance is not as specified, replace the injector.
(d) Reconnect the injector connectors.
(e) Reinstall the throttle body and engine wire covers.
(See steps 5 and 10 to 18 on pages FI±38 to 41)
FI±48
± Fuel System (Injectors)EFI SYSTEM
WhereEverybodyKnowsYourName

COMPONENTS FOR REMOVAL AND INSTALLATION
FI±49EFI SYSTEM ± Fuel System (Injectors)
WhereEverybodyKnowsYourName

REMOVAL OF INJECTORS
(See Components on page FI±49)
1. REMOVE AIR INTAKE CHAMBER (See steps 1 to 16 on pages FI±27 to 32)
2. DISCONNECT FUEL INLET HOSE FROM LH DELIVERY PIPE
Remove the pulsation damper and two gaskets, and discon-
nect the inlet hose.
3. DISCONNECT FUEL RETURN HOSE FROM FUEL RETURN PIPE
4. DISCONNECT EGR PIPE FROM RH CYLINDER HEAD Remove the bolt holding the EGR pipe to the cylinder head,
and disconnect the EGR pipe.
5. DISCONNECT ENGINE WIRE FROM INTAKE MANIFOLD Remove the two bolts, and disconnect the engine wire.
6. DISCONNECT ENGINE WIRE FROM DELIVERY PIPES AND REAR WATER BY±PASS JOINT
(a) Remove the four bolts holding the engine wire to thedelivery pipes, and disconnect the engine wire from the
delivery pipes.
(b) Remove the two bolts holding the engine wire to the rear
water by±pass joint, and disconnect the engine wire
from the rear water by±pass joint.
(c) Remove the two bolts holding the engine wire to the rear
side of the RH cylinder head, and disconnect the engine
wire from the RH cylinder head.
FI±50
EFI SYSTEM
± Fuel System (Injectors)
WhereEverybodyKnowsYourName