1991 LEXUS SC300 air intake

16. REMOVE HEATER WATER VALVE FROM BODY
(a) Disconnect the VSV connector.
(b) Disconnect the bolt holding the engine wire clamp to thewater valve bracket.
(c) Remove the 2 bolts, and disconnect the water valve and bracket assembly.
17. 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
(b) Remove the 2 bolts and 2 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 bypass hose from throttle body
(d) Remove the throttle body gasket.
18. REMOVE AIR INTAKE CHAMBER
(a) Disconnect the following hoses: (1) Brake booster vacuum hose from union on air intake
chamber
(2) Vacuum hose (from VSV for heater water valve) from air
intake chamber
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(b) Remove the bolt, stud bolt and accelerator bracket.
(c) Remove the union bolt, union and 2 gaskets.
(d) Disconnect the following connectors:wCold start injector connector
w VSV connector for fuel pressure control
w Except California:
VSV connector for EGR
(e) Remove the union bolt and 2 gaskets, and disconnect the cold start injector tube from the RH delivery pipe.
CAUTION:
w Put a shop towel under the delivery pipe.
w Slowly loosen the union bolt.
(f) Remove the 2 bolts and gasket, and disconnect the EGR
pipe from the air intake chamber.
(g) Remove the 4 bolts, 8 nut and following parts: (1) VSV for fuel pressure
(2) Except California:VSV for EGR
(3) Transmission throttle cable bracket
(h) Disconnect the DLC1 from the air intake chamber.
(i) Remove the air intake chamber and 4 gaskets.
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12. INSPECT AIR INTAKE CHAMBERUsing a precision straight edge and feeler gauge, measure
the surface contacting the intake manifold for warpage.
Maximum warpage:
0.15 mm (0.0059 in.)
If warpage is greater than maximum, replace the chamber.
13. INSPECT INTAKE MANIFOLD Using a precision straight edge and feeler gauge, measure
the surface contacting the cylinder head and air intake cham-
ber for warpage.
Maximum warpage:
0.15 mm (0.0059 in.)
If warpage is greater than maximum, replace the manifold.
14. INSPECT EXHAUST MANIFOLD Using a precision straight edge and feeler gauge, measure
the surface contacting the cylinder head for warpage.
Maximum warpage:
1.00 mm (0.0394 in.)
If warpage is greater than maximum, replace the manifold.
15. INSPECT CYLINDER HEAD BOLTS Using a caliper gauge, measure the thread outside diameter
of the bolt.
Standard outside diameter:
9.770 ± 9.960 mm (0.3846 ± 0.3921 in.)
Maximum outside diameter: 9.60 mm (0.3780 in.)
If the diameter is less than minimum, replace the bolt.
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25. CONNECT FUEL RETURN HOSE TO FUEL RETURN PIPE
26. CONNECT FUEL INLET HOSE TO LH DELIVERY PIPE
(a) Temporarily connect the fuel inlet hose to the delivery pipe with 2 new gaskets and pulsation damper.
(b) Install the bolt holding the fuel inlet hose to the delivery pipe.
(c) 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.).
27. INSTALL HEATER WATER HOSES Connect the following noses:
(1) Water hose to water bypass pipe
(2) Water hose to rear water bypass joint
28. INSTALL AIR INTAKE CHAMBER
(a) Install the cold start injector, tube and lead wire assembly with
the 3 bolts.
Torque: 7.8 N Vm (80 kgf Vcm, 69 in. Vlbf)
(b) Place 4 new gaskets on the intake manifold.
HINT: Gaskets can only be used twice before being replaced.
(c) Place the air intake chamber on the intake manifold.
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(d) Install a new gasket to the EGR pipe.
(e) Temporarily connect the EGR pipe to the air intake chamberwith the 2 bolts.
HINT: Use bolt 20 mm (0.79 in.) in length.
(f) Temporarily install the air intake and and following parts with the 4 bolts and 8 nuts:
(1) VSV for fuel pressure control
(2) Except California:VSV for EGR
(3) Transmission throttle cable bracket
(4) DLC1
(g) Uniformly tighten the bolts and nuts several passes.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolt 40 mm (1.57 in.) in length.
(h) Tighten the 2 bolts holding the EGR pipe to the air intake chamber.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(i) Tighten the bolt holding the EGR pipe to the RH cylinder
head.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
(j) Connect the cold start injector tube to the RH delivery pipe
with 2 new gaskets and the union bolt.
Torque: 15 N Vm (150 kgf Vcm, 11 ft Vlbf)
(k) Connect the following connectors:
wCold start injector connector
w VSV connector for fuel pressure control
w Except California:
VSV connector for EGR
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(l) Install the accelerator bracket with the bolt and stud bolt.
(m) Install 2 new gaskets and union with the union bolt.
Torque: 29 NVm (300 kgf Vcm, 22 ft Vlbf)
(n) Connect the following hoses:
(1) Brake booster vacuum hose to union on air intake cham-
ber
(2) Vacuum hose (from VSV for heater water valve to air in-
take chamber
29. INSTALL 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)
HINT: Use bolt 40 mm (1.57 in.) in length.
(c) Install the water bypass pipe (from the rear bypass joint) to the clamp on the engine wire cover.
(d) Connect 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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30. INSTALL HEATER WATER VALVE
(a) Install the water valve and bracket assembly with the 2 bolts.
(b) Install the engine wire with the bolt.
(c) Connect the VSV connector.
31. INSTALL IAC VALVE
(a) Install a new gasket and IAC valve with the 2 nuts.
Torque: 18 NVm (185 kgf Vcm, 13 ft Vlbf)
(b) Connect the water bypass hose (from the throttle body) to the
IAC valve.
(c) Connect the IAC valve connector.
32. INSTALL EGR VALVE ADAPTOR
(a) Install a new gasket, the EGR valve adaptor and EGR gas temperature sensor connector bracket with the 2 bolts and 2
nuts.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
HINT: Use bolt 20 mm (0.78 in.) in length.
NOTICE: Do not touch the air intake chamber and adaptor sur-
faces of the gasket with your hand.
(b) Connect the PCV hose to the cylinder head.
(c) Connect the EGR gas temperature sensor connector.
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(c) Connect the following hoses:(1) Water bypass hose to IAC valve
(2) Water bypass hose to water bypass pipe(from rear water bypass joint)
(3) 2 vacuum hoses to VSV for EGR
(d) Install the hose clamp to the PCV hose.
35. INSTALL VACUUM PIPE
(a) Install the vacuum pipe, vacuum hose assembly and EGR water bypass pipe (California) with the 2 bolts.
(b) Connect the following hoses: (1) California: Vacuum hose to throttle body
(2) Except California: 3 vacuum hoses to throttle body
(3) Vacuum hose to fuel pressure regulator
(4) 2 vacuum hoses to VSV for fuel pressure control
(5) Except California: 2 vacuum hoses to EGR vacuum modulator
(6) 2 vacuum hoses (from VSV for EVAP) to vacuum pipe
(7) Vacuum hose (from VSV for fuel pressure) to air intake chamber
(8) Vacuum hose (from charcoal canister) to vacuum pipe
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