LEXUS SC400 1991 Service Repair Manual

VSV for EGR (Exc. USA Spec.)
INSPECTION OF VSV FOR EGR
(See Emission Control Systems on page EC±18)
FI±96
± Electronic Control Syst\
em (VSV for EGR (Exc. USA Spec.))EFI SYSTEM
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EGR Valve (USA Spec. only)
INSPECTION OF VSV FOR EGR
(See Emission Control Systems on page EC±21) FI±97
± Electronic Control System (E\
GR Valve (USA Spec. Only))EFI SYSTEM
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Water Temperature Sensor
COMPONENTS FOR REMOVAL AND
INSTALLATION
FI±98 ± Electronic Control Sys\
tem (Water Temperature Sensor)EFI SYSTEM
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INSPECTION OF WATER TEMPERATURE
SENSOR
1. REMOVE LOWER HIGH±TENSION CORD COVER(See steps 1, 2 and 5 to 12 on pages FI±27 to 29)
2. REMOVE RH IGNITION COIL (a) Disconnect the ignition coil connector.
(b) Remove the two bolts, and disconnect the ignition coil.
(c) Disconnect the cam position sensor connector from the
ignition coil bracket, and remove the ignition coil.
3. DISCONNECT HOSES Disconnect the following hoses:(1) Upper radiator hose from front water by±pass joint
(2) Lower radiator hose from water inlet
(3) Radiator reservoir hose from front water inlet hous-
ing
4. REMOVE WATER INLET AND INLET HOUSING (a) Disconnect the water by±pass hose from the water inlethousing.
(b) Remove the two bolts holding the water inlet housing to the water pump.
(c) Pull out the water inlet and inlet housing assembly.
(d) Remove the O±ring from the water inlet housing.
5. REMOVE WATER TEMPERATURE SENSOR (a) Disconnect the water temperature sensor connector.
(b) Remove the water temperature sensor and gasket. FI±99
EFI SYSTEM
± Electronic Control System (Water Temperature Sensor)
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6. INSPECT WATER TEMPERATURE SENSORUsing an ohmmeter, measure the resistance between the ter-
minals.
Resistance: Refer to the chart graph
If the resistance is not as specified, replace the sensor.
7. REINSTALL WATER TEMPERATURE SENSOR (a) Install a new gasket to the water temperature sensor.
(b) Install the water temperature sensor.
Torque: 20 N Vm (200 kgf Vcm, 14 ft Vlbf)
(c) Connect the water temperature sensor connector.
8. REINSTALL WATER INLET AND INLET HOUSING (a) Remove any old packing (FIPG) material and be carefulnot to drop any oil on the contact surfaces of the water
inlet housing and water pump.
w Using a razor blade and gasket scraper, remove all
the old packing (FIPG) material from the gasket
surfaces and sealing groove.
w Thoroughly clean all components to remove all the
loose material.
w Using a non±residue solvent, clean both sealing
surfaces.
(b) Apply seal packing to the sealing groove of the water
inlet housing as shown in the illustration.
Seal packing: Part No. 08826±00100 or equivalent
w Install a nozzle that has been cut to a 2±3 mm
(0.08±0.12 in.) opening.
HINT: Avoid applying an excessive amount to the surface.
w Parts must be assembled within 5 minutes of
application. Otherwise the material must be
removed and reapplied.
w Immediately remove nozzle from the tube and
reinstall cap.
(c) Install a new O±ring to the water inlet housing.
(d) Apply soapy water to the O±ring.
FI±100
EFI SYSTEM
± Electronic Control System (Water Temperature Sensor)
WhereEverybodyKnowsYourName

(e) Push in the water inlet housing end into the water pumphole.
(f) Install the water inlet and inlet housing assembly with
the two bolts. Alternately tighten the bolts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(g) Connect the water by±pass hose to the water inlet
housing.
9. RECONNECT HOSES Connect the following hoses:(1) Upper radiator hose to front water by±pass joint
(2) Lower radiator hose to water inlet
(3) Radiator reservoir hose to front water inlet housing
10. REINSTALL RH IGNITION COIL (a) Install the ignition coil with the two bolts.
(b) Install the cam position sensor connector to the ignitioncoil bracket.
(c) Connect the ignition coil connector.
11. REINSTALL LOWER HIGH±TENSION CORD COVER (See steps 1 to 13 and 16 to 18 on pages FI±39 to 41)FI±101
EFI SYSTEM
± Electronic Control System (Water Temperature Sensor)
WhereEverybodyKnowsYourName

EGR Gas Temperature Sensor (USA Spec. only)
COMPONENTS FOR REMOVAL AND INSTALLATION
FI±102 ± Electronic Control System (EGR Gas \
Temperature Sensor (USA Spec. only))EFI SYSTEM
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INSPECTION OF EGR GAS
TEMPERATURE SENSOR
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. DRAIN ENGINE COOLANT
3. REMOVE EGR VALVE (a) Disconnect the EGR gas temperature sensor.
(b) Disconnect the following hoses from the EGR valve:(1) Water by±pass hose (from ISC valve)
(2) Water by±pass hose (from rear water by±pass joint)
(c) Remove the two nuts, EGR valve and gasket.
4. REMOVE EGR VALVE ADAPTOR (a) Disconnect the EGR gas temperature sensor.
(b) Disconnect the PCV hose from the EGR valve adaptor.
(c) Remove the two bolts, two nuts, EGR valve adaptor andgasket. FI±103
EFI SYSTEM
± Electronic Control System (EGR Gas Temperature Sensor (USA Spec. only))
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5. REMOVE EGR GAS TEMPERATURE SENSOR FROMEGR VALVE ADAPTOR
(a) Mount the EGR valve adaptor in a vise.
(b) Remove the EGR valve adaptor.
(c) R e m o v e t h e c onnector bracket from the sensor
connector.
6. INSPECT EGR GAS TEMPERATURE SENSOR Using an ohmmeter, measure the resistance between the ter-
minals.
Resistance: 69±89 k
at 50 °C (112 °F)
12±15 k
at 100 °C (212 °F)
2±4 k
at 150 °C (302 °F)
If the resistance is not as specified, replace the sensor.
7. REINSTALL EGR GAS TEMPERATURE SENSOR TO EGR VALVE ADAPTOR
(a) Mount the EGR valve adaptor in a vise.
(b) Install the EGR gas temperature to the adaptor.
Torque: 20 N Vm (200 kgf Vcm, 14 ft Vlbf)
(c) Install the connector bracket to the sensor connector.
8. REINSTALL EGR VALVE ADAPTOR (a) Install a new gasket, the adaptor and connector bracketwith the two bolts, two nuts, EGR valve adaptor and
gasket.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
NOTICE: Do not touch the air intake chamber and adap-
tor surfaces of the gasket with your hand.
(b) Connect the PCV hose to the EGR valve adaptor.
(c) Connect the EGR gas temperature sensor.
FI±104
EFI SYSTEM
± Electronic Control System (EGR Gas Temperature Sensor (USA Spec. only))
WhereEverybodyKnowsYourName

9. REINSTALL EGR VALVE(a) Place a new gasket on the EGR valve adaptor.
NOTICE:
w Do not touch the adaptor and EGR valve surfaces of the
gasket with your hand.
w Align the port holes of the gasket and adaptor. Be careful
of the installation direction.
(b) Install the EGR valve with the two nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(c) Connect the following hoses to the EGR valve:
(1) Water by±pass hose (from ISC valve)
(2) Water by±pass hose (from rear water by±pass joint)
(d) Connect the EGR gas temperature sensor.
10. RECONNECT CABLE FROM NEGATIVE TERMINAL OF BATTERY
11. REFILL WITH ENGINE COOLANT FI±105
EFI SYSTEM
± Electronic Control System (EGR Gas Temperature Sensor (USA Spec. only))
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