LEXUS SC400 1991 Service Repair Manual
Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
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23. REINSTALL THEFT DETERRENT HORN
(a) Install the theft deterrent horn with the bolt.
(b) Connect the connector.
24. REINSTALL RH CYLINDER HEAD COVER
(a) Remove any old packing (FIPG) material.
(b) Apply seal packing to the cylinder head as shown in theillustration.
Seal packing:Part No. 08826±00080 or equivalent
(c) Install the gasket to the cylinder head cover.
(d) Install the seal washer to the bolt.
(e) Install the cylinder head cover with the 8 bolts.
Torque: 5.9 N Vm (60 kgf Vcm, 52 in. Vlbf)
(f) Connect the 4 high±tension cords to the spark plugs.
(g) Connect the front high±tension cord clamp to the lower
high±tension cord cover.
(h) P l a c e t h e f r o n t h i gh±tension cord clamp to the rear
high±tension cord clamp.
(i) Install the 2 bolts holding the high±tension cord clamps to the
cylinder head cover.
(j) Connect the 5 high±tension cords to the front side of the front
high±tension cord clamp.
(k) Connect the No. 2 high±tension cord to the cord clamp on the
front high±tension cord clamp.
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25. REINSTALL LH CYLINDER HEAD COVER
(a) Remove any old packing (FIPG) material.
(b) Apply seal packing to the cylinder head as shown in theillustration.
Seal packing:Part No. 08826±00080 or equivalent
(c) Install the gasket to the cylinder head cover.
(d) Install the seal washer to the bolt.
(e) Install the cylinder head cover with the 8 bolts.
Torque: 5.9 N Vm (60 kgf Vcm, 52 in. Vlbf)
(f) Connect the 2 engine wire connectors.
(g) Connect the 4 injector connectors.
(h) Install the engine wire protector to the 2 brackets on the
delivery pipe.
(i) Connect the 4 high±tension cords to the spark plugs.
(j) Connect the front high±tension cord clamp to the lower high±tension cord cover.
(k) P l a c e t h e f r o n t h i gh±tension cord clamp to the rear
high±tension cord clamp.
(l) Install the 2 bolts holding the high±tension cord clamps to the
cylinder head cover.
(m) Connect the 5 high±tension cords to the front side of the front
high±tension cord clamp.
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(n) Connect the No. 1 high±tension cord to the cord clamp on the
front high±tension cord clamp.
26. REINSTALL THROTTLE BODY
(a) Disconnect the following hoses: (1) PCV hose to throttle body
(2) Water bypass hose to throttle body
(b) Install a new gasket and throttle body with the 2 bolts and 2 nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(c) Install the water bypass pipe (from the rear bypass joint) to
the clamp on the engine wire cover.
(d) Connect the following hoses: (1) Water bypass hose to IAC valve
(2) California:Vacuum hose from throttle body
(3) Except California: 3 vacuum hoses from throttle body
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(e) Connect the following connectors:(1) Throttle position sensor connector
(2) w/ TRAC:Sub±throttle position sensor connector
(3) w/ TRAC: Sub±throttle actuator connector
27. REINSTALL HEATER WATER VALVE
(a) Install the water valve and bracket assembly with the 2 bolts.
(b) Install the engine wire clamp with the bolt.
(c) Connect the VSV connector.
28. REINSTALL RH NO.3 TIMING BELT COVER
(a) Install the 3 gaskets to the timing belt cover.
(b) Fit the portion A of the timing belt cover, matching it with the lower high±tension cord cover.
(c) Install the timing belt cover with the 3 bolts.
29. REINSTALL VSV FOR EVAP SYSTEM Install the VSV with the 2 bolts.
30. REINSTALL LH NO.3 TIMING BELT COVER
(a) Install the 3 gaskets to the timing belt cover.
(b) Install the cord grommet to the high±tension cord (from the LH ignition coil).
(c) Install the cord grommet to the timing belt cover.
(d) Fit the portion A of the timing belt cover, matching it with the lower high±tension cord cover.
(e) Install the timing belt cover with the 4 bolts.
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31. RECONNECT FUEL INLET HOSE TO LH DELIVERY PIPE
(a) Temporarily connect the fuel inlet hose to the delivery pipewith 2 new gaskets and pulsation damper.
(b) Using SST, tighten the pulsation damper.
SST 09631±22020
Torque:
39 NVm (400 kgf Vcm, 29 ft Vlbf)
33 N Vm (340 kgf Vcm, 24 ft Vlbf) for SST
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.).
32. RECONNECT FUEL RETURN HOSE TO FUEL RETURN PIPE
33. RECONNECT PCV HOSE TO LH CYLINDER HEAD
34. REINSTALL RH ENGINE WIRE COVER
(a) Fit portions A and B of the engine wire cover, matching them with the lower high±tension cord cover and No.3 timing belt
cover.
(b) Install the timing belt cover with the bolt.
35. REINSTALL LH ENGINE WIRE COVER
(a) Connect portions A and B of the engine wire cover to the wire
brackets.
(b) Set the VSV (for the fuel pressure) wire in original position.
(c) Fit portions C and D of the engine wire cover, matching them with the lower high±tension cord cover and No.3 timing belt
cover.
(d) Install the timing belt cover with the 2 bolts.
36. REINSTALL UPPER HIGH±TENSION CORD COVER
(a) Fit portion A of the upper high±tension cord cover matching the top of the lower high±tension cord cover.
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(b) Push the front side of the upper high±tension cord cover, andfit 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 2 bolts.
37. REINSTALL INTAKE AIR CONNECTOR
(a) Connect the end portions of the intake air connector to the throttle body and air cleaner hose.
(b) Tighten the 2 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 IAC valve
(2) Air hose (from air control valve on PS pump) to intake air
connector
38. RECONNECT CONTROL CABLES TO THROTTLE BODY Connect the following cables:
(1) Accelerator cable
(2) Transmission throttle control cable
(3) Cruise control actuator cable
39. REINSTALL THROTTLE BODY COVER
(a) Install the thro ttle body cover and hose clamp with the cap nut
and 2 bolts.
(b) Install the EVAP hose to the hose clamp.
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40. RECONNECT NEGATIVE TERMINAL CABLE TOBATTERY
41. REFILL WITH ENGINE COOLANT
42. START ENGINE AND CHECK FOR LEAKS
EG21T±02
IGNITION TIMING INSPECTION
1. REMOVE UPPER HIGH±TENSION CORD COVER
(a) Remove the 2 bolts.
(b) Disconnect the front side claw groove of the upper cord cover
from the claw of lower cord cover, and remove the upper cord
cover.
2. WARM UP ENGINE Allow the engine to warm up to normal operating tempera-
ture.
3. CONNECT TACHOMETER AND TIMING LIGHT TO ENGINE
Connect the tester probe of a tachometer to terminal IG of
the DLC1.
HINT: Set the tachometer to the 4±cylinder range.
NOTICE:
w Never allow the tachometer terminal to touch ground as
it could result in damage to the igniter and/or ignition
coil.
w As some tachometers are not compatible with this
ignition system, we recommend that you confirm the
compatibility of your unit before use.
4. INSPECT IGNITION TIMING
(a) Using SST, connect terminals TE1 and E1 of the DLC 1.
SST 09843±18020
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(b) Connect the tester probe of a timing light to the high ±tension
cord for No.6 cylinder.
(c) Using a timing light, check the ignition timing.
Ignition timing: 8 ± 12 5 BTDC @ idle
(Transmission in neutral position)
If the ignition timing is not as specified, check that following
conditions are normal:
w Throttle valve fully closed
w Continuity between terminals IDL1 and E2 of the throttle
position sensor
w Valve timing
(d) Remove the SST from the DLC1. SST 09843±18020
5. DISCONNECT TACHOMETER AND TIMING LIGHT FROM ENGINE
6. REINSTALL UPPER HIGH±TENSION CORD COVER
(a) Fit portion A of the upper high±tension cord cover matching the top of the lower high±tension cord cover.
(b) Push the front side of the upper high±tension cord cover, and
fit 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 2 bolts.
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EG115±06
IDLE SPEED INSPECTION
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connectedHINT: All vacuum hoses for EGR system, etc. should be prop-
erly connected.
(f) MFI system wiring connectors fully plugged
(g) Ignition timing set correctly
(h) Transmission in neutral position
2. CONNECT TACHOMETER Connect the tester probe of a tachometer to terminal IG of
the DLC1.
HINT: Set the tachometer to the 4±cylinder range.
NOTICE:
w Never allow the tachometer terminal to touch ground as
it could result in damage to the igniter and/or ignition
coil.
w As some tachometers are not compatible with this
ignition system, we recommend that you confirm the
compatibility of your unit before use.
3. INSPECT IDLE SPEED
(a) Race the engine speed at 2,500 rpm for approx. 90 seconds.
(b) Check the idle speed.
Idle speed:
700 + 50 rpm
If the idle speed is not as specified, check the IAC valve.
4. DISCONNECT TACHOMETER
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