fuel LEXUS SC300 1991 Service Owner's Guide

COMPRESSION CHECK
EG21U±02
HINT: If there is lack of power, excessive oil consumption or
poor fuel economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE Allow the engine to warm up to normal operating tempera-
ture.
2. DISCONNECT NEGATIVE TERMINAL CABLE FROM BATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the ªLOCKº posi-
tion and the negative (±) terminal cable is disconnected
from the battery.
3. REMOVE INTAKE AIR CONNECTOR
(a) Disconnect the following hoses: (1) Air hose from IAC valve
(2) Air hose (from air control valve on PS pump) from intake
air connector
(b) Remove the bolt holding the intake air connector to the cylinder head cover.
(c) Remove the 2 hose clamps.
(d) Disconnect the intake air connector from the throttle body
and air cleaner hose, and remove the intake air connector.
4. 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.
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24. REINSTALL RH ENGINE WIRE COVER
(a) Fit portions A and B of the engine wire cover, matching themwith the lower high±tension cord cover and No.3 timing belt
cover.
(b) Install the timing belt cover with the bolt.
25. 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.
26. 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.
27. 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.
EG±42
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30. INSTALL VSV FOR EVAP SYSTEMInstall the VSV with the 2 bolts.
31. INSTALL 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.
32. INSTALL 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.
33. INSTALL 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.
34. INSTALL 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.
EG±68
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9. REMOVE WATER INLET AND INLET HOUSING
(a) Disconnect the water bypass hose from the IAC valve.
(b) Remove the 2 bolts holding the water inlet housing to waterpump.
(c) Pull out the water inlet and inlet housing assembly.
(d) Remove the O±ring from the water inlet housing.
10. REMOVE TIMING BELT REAR PLATES
Remove the 2 bolts and rear plate. Remove the 2 rear plates.
11. REMOVE VACUUM PIPE
(a) Disconnect the following hoses: (1) California:
Vacuum hose from throttle body
(2) Except California: 3 vacuum hoses from throttle body
(3) Vacuum hose from fuel pressure regulator
(4) 2 vacuum hoses from VSV for fuel pressure control
(5) Except California:
2 vacuum hoses from EGR vacuum modulator
(6) 2 vacuum hoses (from VSV for EVAP) from vacuum pipe
(7) Vacuum hose (from VSV for fuel pressure) from air in-
take chamber
(8) Vacuum hose (from charcoal canister) from vacuum pipe
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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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(j) Remove the 3 bolts, the cold start injector, tube, lead wireassembly and gasket.
19. DISCONNECT HEATER WATER HOSES Disconnect the following hoses:
(1) Water hose from water bypass pipe
(2) Water hose from rear water bypass joint
20. DISCONNECT FUEL INLET HOSE FROM DELIVERY PIPE
Remove the pulsation damper and 2 gaskets, and discon-
nect the fuel inlet hose from the delivery pipe.
CAUTION:
w Put a shop towel under the delivery pipe.
w Slowly loosen the union bolts.
21. 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
22. DISCONNECT EGR PIPE FROM RH CYLINDER HEAD Remove the bolt holding the EGR pipe to the RH cylinder
head, and disconnect the EGR pipe.
23. DISCONNECT ENGINE WIRE FROM INTAKE MANIFOLD Remove the 2 bolts, and disconnect the engine wire protector
from the intake manifold.
EG±82
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24. DISCONNECT ENGINE WIRE FROM DELIVERY PIPES,REAR WATER BYPASS JOINT AND RH CYLINDER HEAD
(a) Remove the 4 bolts, and disconnect the engine wire protectors from the delivery pipes.
(b) Remove the 2 bolts, and disconnect the engine wire protector
from the water bypass joint.
(c) Remove the 2 bolts, and disconnect the engine wire protector
from the rear side of the RH cylinder head.
(d) Disconnect the 2 engine wire connectors from the connector bracket on the LH delivery pipe.
(e) Disconnect the 8 injector connectors.
25. REMOVE FUEL RETURN PIPE
(a) Remove the bolt holding the fuel return pipe to the rear side of the LH cylinder head.
(b) Remove the union bolt, 2 gaskets and fuel return pipe.
26. REMOVE DELIVERY PIPES AND INJECTORS
(a) Remove the 4 nuts holding the delivery pipes to intake manifold.
(b) Remove the connector bracket, the 2 delivery pipes and 8 injectors assembly.
NOTICE: Be careful not to drop the injectors when re-
moving the delivery pipes.
(c) Remove the 8 insulators and 4 spacers from the cylinder head.
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(e) Place 8 new insulators and the 4 spacers in position on theintake manifold.
(f) Place the 8 injectors and 2 delivery pipes assembly in position on the intake manifold.
(g) Temporarily install the connector bracket and 4 nuts.
(h) Check that the injectors rotate smoothly.
HINT: If injectors do not rotate smoothly, the probable cause
is incorrect installation of O±rings. Replace the O±rings.
(i) Position the injector connector upward.
(j) Tighten the 4 nuts holding the delivery pipes to the intake manifold.
Torque: 18 N Vm (185 kgf Vcm, 13 ft Vlbf)
21. INSTALL FUEL RETURN PIPE
(a) Temporarily install the fuel return pipe with the bolt, 2 new
gaskets and union bolt.
(b) Tighten the union bolt holding the return pipe to the fuel pressure regulator.
Torque: 35 N Vm (360 kgf Vcm, 26 ft Vlbf)
(c) Tighten the bolt holding the return pipe to the LH cylinder
head.
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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
EG±128
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