1991 LEXUS SC400 sensor

4. (A/T)
REMOVE CUP HOLDERUsing a screwdriver, pry out the rear side of the cup holder.
Remove the cup holder.
5. REMOVE UPPER REAR CONSOLE PANEL Using a screwdriver, pry out the console panel.
6. (A/T)
REMOVE UPPER CONSOLE PANEL (a) Remove the six mounting screws.
(b) Using a screwdriver, pry out the console panel.
7. DISCONNECT SUB±OXYGEN SENSOR CONNECTOR
8. INSPECT HEATER RESIST ANCE OF SUB±OXYGEN
SENSOR
Using an ohmmeter, measure the resistance between the ter-
minals +B and HT.
Resistance: 5.1±6.3
at 20 5C (68 5F)
FI±78±
EFI SYSTEM
Electronic Control System (Sub±Oxygen Sensor (USA Spec. only))
WhereEverybodyKnowsYourName

If the resistance is not as specified, replace the sensor as fol-
lows:
wDisconnect the grommet from the floor panel, and pull
out the wire of the sub±oxygen sensor from the floor
panel.
w Remove the two nuts, cover and sub±oxygen sensor
from the front exhaust pipe.
w Install a new gasket, a new sub±oxygen sensor and the
cover to the front exhaust pipe with the two nuts.
Torque: 18 N Vm (180 kgf Vcm, 13 ft Vlbf)
w Run the wire of the sub±oxygen sensor through the hole
in the floor panel.
9. RECONNECT SUB±OXYGEN SENSOR CONNECTOR
10. (A/T) REINSTALL UPPER REAR CONSOLE PANEL
(a) Fit the console panel to the console box with five clips.
(b) Install the console panel with the six screws.
11. REINSTALL UPPER CONSOLE PANEL Fit the console panel to the console box with the four clips.
12. (A/T) REINSTALL CUP HOLDER
Fit the cup holder to the console box.
±
EFI SYSTEMFI±79
Electronic Control System (Sub±Oxygen Sensor (USA Spec. only))
WhereEverybodyKnowsYourName

13. REINSTALL TRANSMISSION SHIFT LEVER KNOB(A/T)
(a) Slide the lever cover on the lever shaft.
(b) Install the shift lever knob with the two screws.
(c) Attach the l ever cover to the lower side of the lever knob.
14. RECONNECT CABLE TO NEGATIVE TERMINAL OF BAT-
TERY
FI±80
±
EFI SYSTEM
Electronic Control System (Sub±Oxygen Sensor (USA Spec. only))
WhereEverybodyKnowsYourName

INSPECTION OF COLD START
INJECTOR TIME SWITCH
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. REMOVE COLD START INJECTOR TIME SWITCH (a) Disconnect the injector time switch connector.
(b) Remove the injector time switch and gasket.
4. INSPECT COLD START INJECTOR TIME SWITCH Using an ohmmeter, measure the resistance between each
terminal.
Resistance:
STA±STJ 25±45
below 15 °C (59 °F)
65±85
above 30 °C (86 °F)
STA±Ground 25±85

If the resistance is not as specified, replace the switch.
5. REINSTALL COLD START INJECTOR TIME SWITCH (a) Install a new gasket to the injector time switch.
(b) Install the injector time switch.
Torque: 34 N Vm (350 kgf Vcm, 25 ft Vlbf)
(c) Connect the injector time switch connector.
6. REINSTALL RH IGNITION COIL (a) Install the ignition coil with the two bolts.
FI±88
EFI SYSTEM
± Electronic Control System (Cold Start Injector Time Switch)
WhereEverybodyKnowsYourName

(b) Install the cam position sensor connector to the ignitioncoil bracket.
(c) Connect the ignition coil connector.
7. REINSTALL LOWER HIGH±TENSION CORD COVER (See steps 1 to 13 and 16 to 18 on pages FI±39 to 41)FI±89
EFI SYSTEM
± Electronic Control System (Cold Start Injector Time Switch)
WhereEverybodyKnowsYourName

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)
WhereEverybodyKnowsYourName

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