1991 LEXUS SC400 VSV

31. INSTALL LH NO.3 TIMING BELT COVER(a) Install the three gaskets to the timing belt cover.
(b) Install the cord grommet to the high±tension cord.
(c) Install the cord grommet to the timing belt cover.
(d) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(e) Install the timing belt cover with the four bolts.
32. 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.
(b) Install the engine wire cover with the bolt.
33. INSTALL LH ENGINE WIRE COVER (a) Connect portions A and B of the engine wire cover to the
wire cover brackets.
(b) Set the VSV (for Fuel pressure control system) 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.
(b) Install the engine wire cover with the two bolts.
34. 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.
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8. REMOVE WATER BY±PASS OUTLET AND NO. 1 WATERBY±PASS PIPE
(a) Remove the two bolts, water by±pass outlet and No. 1water by±pass pipe.
(b) Remove the three O±rings from the water by±pass outlet and No. 1 water by±pass pipe.
9. REMOVE WATER OUTLET AND NO. 1 BY±PASS HOSE (a) Remove the two nuts, bolt and water outlet.
(b) Disc onnect the No. 1 by±pass hose from the hose
clamp.
10. REMOVE VACUUM CONTROL VALVE SET AND NO. 2 VACUUM PIPE
(a) Disconnect the two connectors from the VSV.
(b) Disconnect the following hoses:(1) Vacuum hose from ACIS vacuum tank
(2) Three vacuum hoses from VSV
(c) Remove the four nuts, vacuum control valve set and
vacuum pipe.
11. REMOVA OIL DIPSTICK GUIDES FOR ENGINE AND TRANSMISSION (A/T)
(a) Disconnect the fuel return hose from the engine oildipstick guide.
(b) Remove the mounting bolt.
(c) Pull out the dipstick guide together with dipstick. Plug the oil pan.
(d) Remove the O±ring from the dipstick guide.
12. REMOVE AIR INTAKE CHAMBER (a) Remove the bolt, nut and intake chamber stay. Removethe No. 1 and No. 2 stays.
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(d) Install the intake chamber stay with the bolt and nut.Install the No. 1 and No. 2 stay.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: The No. 1 stay is marked ºFº and No. 2 stay is marked
with ºRº.
12. INS TALL OIL DIP S TICK GUIDE S FO R ENG INE AND TRANSMISSION (A/T)
(a) Install a new O±ring on the dipstick guide.
(b) Apply soapy water on the O±ring.
(c) Connect the dipstick guide end to the tube of the oil pan.
(d) Install the dipstick guide with a bolt.
(e) Connect the fuel return hose to the engine oil dipstick guide.
13. INSTALL VACUUM CONTROL VALVE SET AND NO. 2 VACUUM PIPE
(a) Install the vacuum control valve set and vacuum pipewith the four nuts.
Torque: 21 N Vm (210 kgf Vcm, 15 ft Vlbf)
(b) Connect the following hoses:
(1) Vacuum hose to ACIS vacuum tank
(2) Three vacuum hoses to VSV
(c) Connect the two connectors to the VSV.
14. INSTALL WATER OUTLET AND NO. 1 BY±PASS HOSE (a) Insert the No. 1 by±pass hose to the intake manifold,and connect the hose to the clamp.
(b) Install the water outlet with the two nuts and bolt.
Torque: 21 N Vm (210 kgf Vcm, 15 ft Vlbf)
15. INSTALL WATER BY±PASS OUTLET AND NO. 1 WATER
BY±PASS PIPE
(a) Install two new O±rings to the No. 1 water by±pass pipe.
(b) Install a new O±ring and the water by±pass outlet with the two bolts.
Torque: 8.8 N Vm (90 kgf Vcm, 78 in. Vlbf)
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9. REMOVE TIMING BELT REAR PLATESRemove the two bolts and rear plate. Remove the two rear
plates.
10. REMOVE VACUUM PIPE (a) Disconnect the following hoses:(1) (USA Spec.)
Vacuum hose from throttle body
(2) (Exc. USA Spec.) Three vacuum hoses from throttle body
(3) Vacuum hose from fuel pressure regulator
(4) Two vacuum hoses from VSV for fuel pressure con-
trol system
(5) (Exc. USA Spec.) Two vacuum hoses from EGR vacuum modulator
(6) Two vacuum hoses (from VSV for EVAP system)
from vacuum pipe
(7) Vacuum hose (from VSV for fuel pressure control system) from air intake chamber
(8) Vacuum hose (from charcoal canister) from vacu-
um pipe.
(b) Remove the two bolts, the vacuum pipe and vacuum hoses assembly.
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11. (USA Spec.)REMOVE EGR VALVE
(a) Disconnect the EGR valve connector.
(b) Disconnect the following hoses:(1) Water by±pass pipe hose from ISC valve
(2) Water by±pass hose from water by±pass pipe (from rear water by±pass joint)
(c) Remove the two nuts, EGR valve and gasket.
12. (Exc. USA Spec.) REMOVE EGR VALVE AND VACUUM MODULATOR
(a) Disconnect the hose clamp (A) from the PCV hose.
(b) Disconnect the following hoses:(1) Water by±pass pipe hose from ISC valve
(2) Water by±pass hose from water by±pass pipe (from rear water by±pass joint)
(3) Two vacuum hoses from VSV for EGR system
(c) Remove the bolt, two nuts, the EGR valve, vacuum modulator assembly and gasket.
13. REMOVE EGR VALVE ADAPTOR (a) Disconnect the PCV hose from the cylinder head.
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(b) Remove the two bolts, two nuts, adaptor and gasket.
(c) (USA Spec. only)Disconnect the EGR gas temperature sensor connec-
tor.
14. REMOVE ISC VALVE (a) Disconnect the ISC valve connector.
(b) Disconnect the water by±pass hose from the ISC valve.
(c) Remove the two nuts, ISC valve and gasket.
15. DISCONNECT HEATER WATER VALVE FROM BODY (a) Disconnect the VSV connector.
(b) Remove the bolt holding the engine wire clamp to thewater valve bracket.
(c) Remove the two bolts, and disconnect the water valve and bracket assembly.
16. REMOVE THROTTLE BODY (a) Disconnect the following connectors:(1) Throttle position sensor connector
(2) (w/ TRAC)
Sub±throttle position sensor connector
(3) (w/ TRAC) Sub±throttle actuator connector
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(b) Remove the two mounting bolts and two mounting nuts,and disconnect the throttle body from the air intake
chamber.
(c) Disconnect the following hoses, and remove the throttle body:
(1) PCV hose from throttle body
(2) Water by±pass hose from throttle body
(d) Remove the throttle body gasket.
17. DISCONNECT VACUUM HOSES Disconnect the following hoses:(1) Vacuum hose from brake booster union
(2) Vacuum hose (from VSV for heater water valve)
from air intake chamber
18. REMOVE ACCELERATOR BRACKET Remove the bolt, stud bolt and bracket.
19. REMOVE BRAKE BOOSTER UNION
Remove the union bolt, union and two gaskets.
20. REMOVE AIR INTAKE CHAMBER (a) Disconnect the following connectors:w Cold start injector connector
w VSV connector for fuel pressure control system
w (Exc. USA Spec.)
VSV connector for EGR system
(b) Remove the union bolt and two gaskets, and disconnect
the cold start injector tube from the RH delivery pipe.
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(c) Remove the two bolts and gaskets, and disconnect theEGR pipe from the air intake chamber.
(d) Remove the four mounting bolts, eight mounting nuts and following parts:
(1) VSV for fuel pressure control system
(2) (Exc. USA Spec.)
VSV for EGR system
(3) A/T throttle cable bracket
(e) Disconnect the check (ºDIAGNOSISº) connector from
the intake chamber.
(f) Remove the air intake chamber and four gaskets.
(g) Remove the three bolts, the cold start injector, tube, lead
wire assembly and gasket.
21. DISCONNECT HEATER WATER HOSES Disconnect the following hoses:(1) Water hose from water by±pass pipe
(2) Water hose from rear water by±pass joint
22. DISCONNECT FUEL INLET HOSE FROM LH DELIVERY PIPE
Remove the pulsation damper and two gaskets, and discon-
nect the inlet hose.
23. D I S C O N N E C T F U E L R E T U R N H O S E F R O M F U E L RETURN PIPE
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