engine LEXUS SC400 1991 Service Repair Manual
[x] Cancel search | Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
Page 1877 of 4087

REMOVAL OF INJECTORS
(See Components on page FI±49)
1. REMOVE AIR INTAKE CHAMBER (See steps 1 to 16 on pages FI±27 to 32)
2. DISCONNECT FUEL INLET HOSE FROM LH DELIVERY PIPE
Remove the pulsation damper and two gaskets, and discon-
nect the inlet hose.
3. DISCONNECT FUEL RETURN HOSE FROM FUEL RETURN PIPE
4. DISCONNECT EGR PIPE FROM RH CYLINDER HEAD Remove the bolt holding the EGR pipe to the cylinder head,
and disconnect the EGR pipe.
5. DISCONNECT ENGINE WIRE FROM INTAKE MANIFOLD Remove the two bolts, and disconnect the engine wire.
6. DISCONNECT ENGINE WIRE FROM DELIVERY PIPES AND REAR WATER BY±PASS JOINT
(a) Remove the four bolts holding the engine wire to thedelivery pipes, and disconnect the engine wire from the
delivery pipes.
(b) Remove the two bolts holding the engine wire to the rear
water by±pass joint, and disconnect the engine wire
from the rear water by±pass joint.
(c) Remove the two bolts holding the engine wire to the rear
side of the RH cylinder head, and disconnect the engine
wire from the RH cylinder head.
FI±50
EFI SYSTEM
± Fuel System (Injectors)
WhereEverybodyKnowsYourName
Page 1878 of 4087

(d) Disconnect the two engine wire connectors from theconnector bracket on the front side of the LH delivery
pipe.
(e) Disconnect the eight injector connector.
7. REMOVE FUEL RETURN PIPE (a) Remove the bolt holding the return pipe to the LHcylinder head.
(b) Remove the union bolt and two gaskets and return pipe.
8. REMOVE DELIVERY PIPES AND INJECTORS (a) Remove the four nuts holding the delivery pipe to theintake manifold.
(b) Remove the connector bracket, the two delivery pipes and eight injector assembly, four spacers and eight
insulators.
NOTICE: Be careful not to drop the injectors, when re-
moving the delivery pipe.
(c) Pull out the eight injectors from the delivery pipes.
(d) Remove the O±ring and grommet from each injector. FI±51
EFI SYSTEM
± Fuel System (Injectors)
WhereEverybodyKnowsYourName
Page 1880 of 4087

(g) Install the grommet and a new O±ring to the injector.
(h) Connect SST (hose) to the injector with SST (union),and hold the injector and union with SST (clamp).
SST 09268±41045
(i) Put the injector into the graduated cylinder.
HINT: Install a suitable vinyl hose onto the injector to prevent
gasoline from splashing out.
(j) Using SST, connect terminals +B and FP of the check (ºDIAGNOSISº) connector.
SST 09843±18020
(k) Reconnect the cable to negative (±) terminal of battery.
(l) Turn the ignition switch ON.
NOTICE: Do not start the engine.
(m) Connect SST (wire) to the injector and battery for 15 seconds, and measure the injection volume with a
graduated cylinder. Test each injector two or three
times.
SST 09842±30070
Volume: 55±70 cc (3.4±4.3 cu in.) per 15 sec.
Difference between each injector:
10 cc (0.6 cu in.) or less
If the injection volume is not as specified, replace the injector.
2. INSPECT LEAKAGE (a) In the condition above, disconnect the test probes ofSST (wire) from the battery and check the fuel leakage
from the injector.
SST 09842±30070
Fuel drop: One drop or less per minute
(b) Disconnect the battery negative (±) cable.
(c) Remove SST.
SST 09268±41045 and 09843±18020
(d) Reconnect the fuel inlet hose to the fuel tube.
SST 09631±22020
Torque: 30 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Use a torque wrench with a fulerum length of 30 cm
(11.81 in.). FI±53
EFI SYSTEM
± Fuel System (Injectors)
WhereEverybodyKnowsYourName
Page 1883 of 4087

4. INSTALL ENGINE WIRE TO DELIVERY PIPES, REARWATER BY±PASS JOINT AND RH CYLINDER HEAD
(a) Connect the eight injector connectors.
(b) C onnect the two engine wire connectors to the
connector bracket on the LH delivery pipe.
(c) Install the engine wire to the RH cylinder head with the two bolts.
(d) Install the engine wire to the rear water by±pass joint
with the two bolts.
(e) Install the engine wire to the delivery pipes with the four bolts.
5. INSTALL ENGINE WIRE TO INTAKE MANIFOLD Install the engine wire with the two bolts.
6. TEMPORARILY INSTALL EGR PIPE TO RH CYLINDER HEAD
Temporarily Install the EGR pipe with the bolt.
FI±56
EFI SYSTEM
± Fuel System (Injectors)
WhereEverybodyKnowsYourName
Page 1885 of 4087

Idle Speed Control (ISC) Valve
ON±VEHICLE INSPECTION
INSPECT ISC VALVE FOR OPERATING SOUNDCheck that there is a clicking sound immediately after stop-
ping the engine.
If the rpm operation is not as specified, check the ISC valve,
wiring and ECU.
±
EFI SYSTEM Air Induction System (Idle Speed Control (ISC) Valve)FI±53
WhereEverybodyKnowsYourName
Page 1888 of 4087

Acoustic Control Induction System (ACIS)
ON±VEHICLE INSPECTION
INSPECT IACV(a) Using a 3±way connector, connect vacuum gauge to the
actuator hose.
(b) Start the engine.
(c) While the engine is idling, check that the vacuum gauge needle does not move.
(d) Repidly depress the accelerator pedal to fully open position and check that the vacuum gauge needle
momentarily fluctuates approx. 53.3 kPa (400 mmHg,
15.75 in.Hg). (The actuator rod is pulled out.)
FI±56
±
EFI SYSTEM Air Induction System (Acoustic Control Induction System (ACIS)
WhereEverybodyKnowsYourName
Page 1890 of 4087

3. REMOVE VACUUM CONTROL VALVE SET(a) Disconnect the connector from the VSV.
(b) Disconnect the following hoses:(1) Vacuum hose from VSV
(2) Vacuum hose from vacuum pipe
(c) Remove the two nuts and vacuum control valve set.
4. REMOVE VACUUM TANK AND VSV Remove the screw, vacuum hose and VSV from the vacuum
tank.
5. REMOVE OIL DIPSTICK FOR ENGINE
6. DISCONNECT NO. 2 VACUUM PIPE Remove the two nuts and disconnect the vacuum pipe.
7. REMOVE EGR PIPE (a) Loosen the union nut.
(b) Remove the two bolts, EGR pipe and gasket.
8. REMOVE AIR INTAKE CHAMBER (a) Disconnect the following hoses:(1) Vacuum hose from brake booster union
(2) Air hose (from charcoal canister)
(3) Vacuum hose from vacuum pipe
(4) Vacuum sensing hose
(5) Air hose (from PS air control valve)
FI±58
±
EFI SYSTEM
Air Induction System (Acoustic Control Induction System (ACIS)
WhereEverybodyKnowsYourName
Page 1894 of 4087

3. INSTALL NO.2 VACUUM PIPEInstall the vacuum pipe with the two nuts.
Torque: 21 N Vm (210 kgf Vcm, 15 ft Vlbf)
4. INSTALL OIL DIPSTICK FOR ENGINE
5. INSTALL VACUUM TANK AND VSV
(a) Install the VSV with the screw on the vacuum tank.
Torque: 8.8 N Vm (90 kgf Vcm, 78 in. Vlbf)
(b) Install the vacuum hose.
6. INSTALL VACUUM CONTROL VALVE SET (a) Install the vacuum control valve set with the two nuts.
Torque: 21 N Vm (210 kgf Vcm, 15 ft Vlbf)
(b) Connect the following hoses:
(1) Vacuum hose to VSV
(2) Vacuum hose to vacuum pipe
(c) Connect the connector to the VSV.
7. (A/T) INSTALL DIPSTICK GUIDE FOR TRANSMISSION
(a) Install a new O±ring on the dipstick guide.
(b) Apply soapy on the O±ring.
(c) Connect the dipstick guide end to the tube of the oil pan,
and install the dipstick guide with the bolt.
(d) Install the dipstick.
8. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
FI±62
±
EFI SYSTEM
Air Induction System (Acoustic Control Induction System (ACIS)
WhereEverybodyKnowsYourName
Page 1896 of 4087

REMOVAL OF FUEL PRESSURE
PULSATION DAMPER
(See Component on page FI±58)
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OF BATTERY
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 the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE UPPER HIGH±TENSION CORD COVER (a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord coverfrom the claw of the lower cover, and remove the cord
cover.
3. REMOVE LH ENGINE WIRE COVER Remove the two bolts and engine wire cover.
4. REMOVE FUEL PRESSURE PULSATION DAMPER (a) Remove the pulsation damper and upper gasket.
(b) Disconnect the fuel inlet hose from the delivery pipe,and remove the lower gasket. FI±59
EFI SYSTEM
± Fuel System (Fuel Pressure Pulsation Damper)
WhereEverybodyKnowsYourName
Page 1897 of 4087

INSTALLATION OF FUEL PRESSURE
PULSATION DAMPER
(See Components on page FI±58)
1. INSTALL FUEL PRESSURE PULSATION DAMPER Using SST, install two new gaskets, the inlet hose and pulsa-
tion damper.
SST 09612±24014 (09617±24011)
Torque: 39 N Vm (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.)
2. INSTALL LH ENGINE WIRE COVER
(a) Connect portions A and B engine wire cover to the wirebrackets.
(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.
(d) Install the engine wire cover with the two bolts.
3. INSTALL UPPER HIGH±TENSION CORD COVER (a) Fit portion A of the upper high±tension cover, matching
it 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.
4. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
5. CHECK FOR FUEL LEAKS (See page FI±16)
FI±60
EFI SYSTEM
± Fuel System (Fuel Pressure Pulsation Damper)
WhereEverybodyKnowsYourName