ESP LEXUS SC300 1991 Service Owner's Manual

PRECAUTIONS
1. Before working on the fuel system, disconnect the cablefrom negative (±) terminal of the battery.
HINT: Any diagnostic code retained by the computer will be
erased when the battery terminal is removed. Therefore, if
necessary, read the diagnosis before removing the battery
terminal.
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.
2. Do not smoke or work on open flame when working on the fuel system.
3. Keep gasoline away from rubber or leather parts.
INSPECTION PRECAUTIONS
MAINTENANCE PRECAUTIONS
1. CHECK CORRECT ENGINE TUNE±UP (See page EM±8)
2. PRECAUTIONS WHEN CONNECTING GAUGE (a) Use the battery as the power source for the timing light,tachometer, etc.
(b) Connect the test probe of a tachometer to the terminal IG
of the check connector.
3. IN EVENT OF ENGINE MISFIRE, FOLLOWING PRECAUTIONS SHOULD BE TAKEN
(a) Check proper connection of battery terminals, etc.
(b) Handle high±tension cords carefully.
(c) After repair work, check that the ignition coil terminalsand all other ignition system lines are reconnected
securely.
(d) When cleaning the engine compartment, be especially careful to protect the electrical system from water.
4. PRECAUTIONS WHEN HANDLING OXYGEN SENSOR (a) Do not allow oxygen sensor to drop or hit against anobject.
(b) Do not allow the sensor to come into contact with water.
±
EFI SYSTEM Precautions, Inspection PrecautionsFI±11
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IF VEHICLE IS EQUIPPED WITH MOBILE
RADIO SYSTEM (HAM, CB, ETC.)
The ECU has been designed so that it will not be affected by out-
side interference. However, if your vehicle is equipped with a CB
radio transceiver, etc. (even one with about 10 W output), it may,
at times, have an effect upon ECU operation, especially if the an-
tenna and feeder are installed nearby.
Therefore, observe the following precautions:
1. Install the antenna as far away as possible from the ECU. The ECU is located on the floor panel on the passenger side
so the antenna should be installed at the rear of the vehicle.
2. Keep the antenna feeder as far away as possible from the ECU wires±at least 20 cm (7.87 in.) ±and, especially, do not
wind them together.
3. Check that the feeder and antenna are properly adjusted.
4. Do not equip your vehicle with a powerful mobile radio
system.
5. Do not open the cover or the case of the ECU unless absolutely necessary. (If the IC terminals are touched, the IC
may be destroyed by static electricity.)
AIR INDUCTION SYSTEM
1. Separation of the engine oil dipstick, oil filler cap, PCV hose,
etc. may cause the engine to run out of tune.
2. Disconnection, looseness or cracks in the parts of the air
induction system between the throttle body and cylinder
head will cause air suction and cause the engine to run out
of tune.
ELECTRONIC CONTROL SYSTEM
1. Before removing EFI wiring connectors, terminals, etc., firstdisconnect the power by either turning the ignition switch
OFF or disconnecting the battery terminals.
HINT: Always check the diagnosis code before disconnecting
the battery terminals.
2. When installing the battery, be especially careful not to
incorrectly connect the positive (+) and negative (±) cables.
3. Do not permit parts to receive a severe impact during removal or installation. Handle all EFI parts carefully, especially the
ECU.
4. Do not be careless during troubleshooting as there are numerous transistor circuits and even slight terminal contact
can cause further troubles.
5. Do not open the ECU cover.
6. When inspecting during rainy weather, take care to prevent entry of water. Also, when washing the engine compartment,
prevent water from getting on the EFI parts and wiring
connectors.
7. Parts should be replaced as an assembly.
FI±12
±
EFI SYSTEM Inspection Precautions
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PRECAUTIONS
1. Before working on the fuel system, disconnect the cablefrom negative (±) terminal of the battery.
HINT: Any diagnostic code retained by the computer will be
erased when the battery terminal is removed. Therefore, if
necessary, read the diagnosis before removing the battery
terminal.
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 negative (±) terminal
cable is disconnected from the battery.
2. Do not smoke or work on open flame when working on the fuel system.
3. Keep gasoline away from rubber or leather parts.
INSPECTION PRECAUTIONS
MAINTENANCE PRECAUTIONS
1. CHECK CORRECT ENGINE TUNE±UP (See page EM±8)
2. PRECAUTIONS WHEN CONNECTING GAUGE (a) Use the battery as the power source for the timing light,tachometer, etc.
(b) Connect the test probe of a tachometer to the terminal IG of the check connector.
3. IN EVENT OF ENGINE MISFIRE, FOLLOWING PRECAUTIONS SHOULD BE TAKEN
(a) Check proper connection of battery terminals, etc.
(b) Handle high±tension cords carefully.
(c) After repair work, check that the ignition coil terminalsand all other ignition system lines are reconnected
securely.
(d) When cleaning the engine compartment, be especially careful to protect the electrical system from water.
4. PRECAUTIONS WHEN HANDLING OXYGEN SENSOR (a) Do not allow oxygen sensor to drop or hit against anobject.
(b) Do not allow the sensor to come into contact with water.
FI±12
± Precautions, Inspection PrecautionsEFI SYSTEM
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IF VEHICLE IS EQUIPPED WITH MOBILE
RADIO SYSTEM (HAM, CB, ETC.)
The ECU has been designed so that it will not be affected by out-
side interference. However, if your vehicle is equipped with a CB
radio transceiver, etc. (even one with about 10 W output), it may,
at times, have an effect upon ECU operation, especially if the an-
tenna and feeder are installed nearby.
Therefore, observe the following precautions:
1. Install the antenna as far away as possible from the ECU. The
ECU is located on the floor panel on the passenger side so
the antenna should be installed at the rear of the vehicle.
2. Keep the antenna feeder as far away as possible from the ECU wires±at least 20 cm (7.87 in.)±and, especially, do not
wind them together.
3. Check that the feeder and antenna are properly adjusted.
4. Do not equip your vehicle with a powerful mobile radio
system.
5. Do not open the cover or the case of the ECU unless absolutely necessary. (If the IC terminals are touched, the IC
may be destroyed by static electricity.)
AIR INDUCTION SYSTEM
1. Separation of the engine oil dipstick, oil filler cap, PCV hose,
etc. may cause the engine to run out of tune.
2. Disconnection, looseness or cracks in the parts of the air induction system between the throttle body and cylinder
head will cause air suction and cause the engine to run out
of tune.
ELECTRONIC CONTROL SYSTEM
1. Before removing EFI wiring connectors, terminals, etc., firstdisconnect the power by either turning the ignition switch
OFF or disconnecting the battery terminals.
HINT: Always check the diagnosis code before disconnecting
the battery terminals.
2. When installing the battery, be especially careful not to
incorrectly connect the positive (+) and negative (±) cables.
3. Do not permit parts to receive a severe impact during removal or installation. Handle all EFI parts carefully, especially the
ECU.
4. Do not be careless during troubleshooting as there are numerous transistor circuits and even slight terminal contact
can cause further troubles.
5. Do not open the ECU cover.
6. When inspecting during rainy weather, take care to prevent entry of water. Also, when washing the engine compartment,
prevent water from getting on the EFI parts and wiring
connectors.
7. Parts should be replaced as an assembly. FI±13
EFI SYSTEM
± Inspection Precautions
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26. FINAL INSPECTION
(a) Check the operation of the body parts:wHood:
Auxiliary catch operates properly Hood locks securely
when closed
w Doors:
Door locks operate properly Doors close properly
w Luggage compartment door:
Door lock operates properly
w Seats:
Seat adjusts easily and locks securely in any position
Front seat back locks securely in any position Folding±
down rear seat backs lock securely
(b) Be sure to deliver a clean car. Especially check: wSteering wheel
w Shift lever knob
w All switch knobs
w Seats
MA±18
±
MAINTENANCE (1UZ ± FE)
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GENERAL MAINTENANCE
MA00M±03
There are the maintenance and inspection
items which are considered to be the owner's
responsibility. They can be performed by the
owner or be can have them done at a service
shop. These items include those which should
be checked on a daily basis, those which, in
most cases, do not require (special) tools and
those which are considered to be reasonable
for the owner to perform. Items and procedures
for general maintanance are as follows:
MA00P±04
OUTSIDE VEHICLE
1. TIRES
(a) Check the pressure with a gauge. Adjust ifnecessary.
(b) Check for cuts, damage or excessive wear.
2. WHEEL NUTS Wheel checking the tires, check the nuts for
looseness or for missing nuts. If necessary,
tighten them.
3. TIRE ROTATION It is recommended that tires be rotated every
12,000 km (7,500 miles).
4. WINDSHIELD WIPER BLADES Check for wear or cracks whenever they do not
wipe clean. Replace if necessary.
5. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or
other fluid.
(b) If you smell gasoline fumes or notice any leak, have the cause found and corrected.
6. DOORS AND ENGINE HOOD
(a) Check that all doors including the trunk lid operate smoothly, and that all latches lock
securely.
(b) Check that the engine hood secondary latch secures the hood from opening when the
primary latch is released.
MA00R±05
INSIDE VEHICLE
7. LIGHTS
(a) C h e c k t h a t t h e h eadlights, stop lights,
tail±lights, turn signal lights, and other lights
are all working. (b) Check the headlight aiming.
8. WARNING LIGHT AND BUZZERS
Check that all warning lights and buzzers func-
tion properly.
9. HORN Check that it is working.
10. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
11. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
12. WINDSHIELD DEFROSTER Check that the air comes out from the defroster
outlet when operating the heater air condition-
er at defroster mode.
13. REAR VIEW MIRROR
Check that it is mounted securely.
14. SUN VISORS Check that they move freely and are mounted
securely.
15. STEERING WHEEL Check that it has the specified freeplay. Be
alert for changes in steering condition, such as
hard steering, excessive freeplay or strange
noise.
16. SEATS
(a) Check that all front seat controls such as seat adjusters, seatback recliner, etc. operate
smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the locks hold securely in any latched position.
(d) Check that the head restraints move up and
down smoothly and that the locks hold securely
in ay latches position.
(e) For folding±down rear seat backs, check that the latches lock securely.
17. SEAT BELTS
(a) Ch e ck th a t th e se a t be lt syste m su ch as buckles, retractors and anchors operate
properly and smoothly.
(b) Check that the belt webbing is not cut, frayed,
worn or damaged.
18. ACCELERATOR PEDAL Check the pedal for smooth operation and un-
even pedal effort or catching.
±
MAINTENANCE (1UZ ± FE)MA±19
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If using a new propeller shaft w / Phasemarks:
Install the propeller shaft phasemarks and differential phase-
marks so that their respective alignment phasemarks match.
If the propeller shaft phasemarks and differential phase-
marks do not align, install the propeller shaft and differential
alignment phasemarks are as close together as possible.
w / o Phasemarks:
Install the propeller shaft.
(See page PR±12)
(h) Torque the center support bearing set bolts.
Torque: 49 N Vm (500 kgf Vcm, 36 ft Vlbf)
HINT: Adjust the center support bearing to keep the dimen-
sion within the limits, as shown.
Under the same condition, check if the center line of the cen-
ter support bearing is at right angles to the shaft axial direc-
tion.
(i) Using SST, tighten the adjusting nut. SST 09922±10010
Torque: 48 N Vm (490 kgf Vcm, 35 ft Vlbf)
HINT: Use a torque wrench with a fulcrum length of 350 mm
(13.8 in.).
2. INSPECT JOINT ANGLE (See page PR±15)
NOTICE: The joint angle should by all means be checked
when the propeller shaft is removed and installed.
3. INSTALL CROSSMEMBER BRACE Install the center floor crossmember brace and torque the 4
bolts.
Torque: 13 N Vm (130 kgf Vcm, 8 ft Vlbf)
±
PROPELLER SHAFT PROPELLER SHAFTPR±13
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(b) Remove SST.
(c) Insert the yoke into the transmission.
(d) Align the matchmarks and install the propeller shaft on thedifferential with the 3 bolts, washers and nuts.
NOTICE: Bolts should be inserted from the propeller
shaft side.
Torque: 79 N Vm (805 kgf Vcm, 58 ft Vlbf)
If using a new propeller shaft (w/ Phasemarks)
Install the propeller shaft phasemarks and differential phase-
marks so that their respective alignment phasemarks match.
If the propeller shaft phasemarks and differential phase-
marks do not align, install the propeller shaft and differential
alignment phasemarks are as close together as possible.
(w/o Phasemarks)
Install the propeller shaft.
(See page PR±28)
±
PROPELLER SHAFT PROPELLER SHAFTPR±29
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(2) If the seating is too low on the valve face, use 755
and 45 5 cutters to correct the seat.
(d) Hand±lap the valve and valve seat with an abrasive compound.
(e) After hand±lapping, clean the valve and valve seat.
9. INSPECT VALVE SPRINGS (a) Using a steel square, measure the squareness of thevalve spring.
Maximum squareness: 2.0 mm (0.079 in.)
If squareness is greater than maximum, replace the valve
spring.
(b) Using a vernier caliper, measure the free length of the
valve spring.
Free length: 43.6 mm (1.717 in.)
If the free length is not as specified, replace the valve spring.
(c) Using a spring tester, measure the tension of the valvespring at the specified installed length.
Installed tension (at 32.9 mm (1.295 in.):
186±206 N (19.0±21.0 kgf, 41.9±46.3 lbf)
If the installed tension is not as specified, replace the valve
spring.
EM±84
±
ENGINE MECHANICAL Cylinder Heads
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ASSEMBLY OF PISTON AND
CONNECTING ROD ASSEMBLIES
1. ASSEMBLE PISTON AND CONNECTING ROD(a) Using a small screwdriver, install a new snap ring on one
side of the piston pin hole.
(b) Gradually heat the piston to about 60 °C (140 °F).
(c) Position the piston front mark with respect to the outside
mark on the connecting rod as shown in the diagram.
NOTICE: The installation direction of the piston and con-
necting rod are different for the RH and LH banks. The RH
piston is marked with ºRº, the LH piston with ºLº.
(d) Align the piston pin holes of the piston and connecting rod, and push in the piston pin with your thumb.
(e) Using a small screwdriver, install a new snap ring on the
other side of the piston pin hole.
EM±154
±
ENGINE MECHANICAL Cylinder Block
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