TOYOTA SUPRA 1995 Service Repair Manual

IF VEHICLE IS EQUIPPED WITH MOBILE
RADIO SYSTEM (HAM, CB, ETC.)
If the vehicle is equipped with a mobile communication sys-
tem, refer to the precaution in the IN section.
AIR INDUCTION SYSTEM
1. Separation of the engine oil dipstick, oil filler cap, PCV hose,
etc. may cause the engine to run out of tune.
2. Disconnection, looseness or cracks in the parts of the air
induction system between the throttle body and cylinder
head will cause air suction and cause the engine to run out
of tune.
ELECTRONIC CONTROL SYSTEM
1. Before removing SFI wiring connectors, terminals, etc., first
disconnect the power by either turning the ignition switch
OFF or disconnecting the negative (±) terminal cable from the
battery.
HINT: Always check the diagnostic trouble code before dis-
connecting the negative (±) terminal cable from the battery.
2. When installing the battery, be especially careful not to
incorrectly connect the positive (+) and negative (±) cables.
3. Do not permit parts to receive a severe impact during removal
or installation. Handle all SFI parts carefully, especially the
ECM.
4. Do not be careless during troubleshooting as there are
numerous transistor circuits and even slight terminal contact
can cause further troubles.
5. Do not open the ECM cover.
6. When inspecting during rainy weather, take care to prevent
entry of water. Also, when washing the engine compartment,
prevent water from getting on the SFI parts and wiring
connectors.
7. Parts should be replaced as an assembly.
8. Care is required when pulling out and inserting wiring
connectors.
(a) Release the lock and pull out the connector, pulling on the
connectors.
(b) Fully insert the connector and check that it is locked.
± ENGINESFI SYSTEM (2JZ±GTE)EG±261

9. Use SST for inspection or test of the injector or its wiring
connector.
SST 09842±30060
FUEL SYSTEM
1. When disconnecting the high pressure fuel line, a large
amount of gasoline will spill out, so observe the following
procedures:
(a) Disconnect the fuel pump connector.
(b) Start the engine. After the engine has stopped on its own,
turn off the ignition switch.
(c) Put a container under the connection.
(d) Slowly loosen the connection.
(e) Disconnect the connection.
(f) Plug the connection with a rubber plug.
(g) Reconnect the fuel pump connector.
2. When connecting the flare nut or union bolt on the high
pressure pipe union, observe the following procedures:
Union Bolt Type:
(a) Always use a new gasket.
(b) Tighten the union bolt by hand.
(c) Tighten the union bolt to the specified torque.
Torque: 29 NVm (300 kgfVcm, 22 ftVlbf)
Flare Nut Type:
(a) Apply a light coat of engine oil to the flare nut, and tighten the
flare nut by hand.
(b) Using SST, tighten the flare nut to specified torque.
SST 09631±22020
Torque: 30 NVm (310 kgfVcm, 22 ftVlbf)
HINT: Use a torque wrench with a fulcrum length of 30 cm
(11.81 in.). EG±262
± ENGINESFI SYSTEM (2JZ±GTE)

3. Observe the following precautions when removing and
installing the injectors.
(a) Never reuse the O±ring.
(b) When placing a new O±ring on the injector, take care not to
damage it in any way.
(c) Coat a new O±ring with spindle oil or gasoline before
installing±never use engine, gear or brake oil.
4. Install the injector to the delivery pipe and intake manifold as
shown in the illustration.
5. Check that there are no fuel leaks after doing maintenance
anywhere on the fuel system.
(a) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020
(b) With engine stopped, turn the ignition switch ON.
(c) Pinch the fuel return hose.
The pressure in the high pressure line will rise to approx. 392
kPa (4 kgf/cm
2, 57 psi). In this state, check to see that there
are no leaks from any part of the fuel system.
NOTICE: Always pinch the hose. Avoid bending as it may
cause the hose to crack.
(d) Turn the ignition switch OFF.
(e) Remove the SST from the DLC1.
SST 09843±18020
± ENGINESFI SYSTEM (2JZ±GTE)EG±263

FUEL PUMP
ON±VEHICLE INSPECTION
1. CHECK FUEL PUMP OPERATION
(a) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020
(b) Turn the ignition switch ON.
NOTICE: Do not start the engine.
(c) Check that there is pressure in the fuel inlet hose from the fuel
filter.
HINT: If there is fuel pressure, you will hear the sound of fuel
flowing.
If there is no pressure, check the following parts:
wFuses
wEFI No.2 relay
wFuel pump
wECM
wWiring connections
(d) Turn the ignition switch OFF
(e) Remove the SST from the DLC1.
SST 09843±18020
2. CHECK FUEL PRESSURE
(a) Check the battery voltage is above 12 V.
(b) Disconnect the negative (±) terminal cable from the battery.
(c) Remove the union bolt and 2 gaskets, disconnect the fuel
inlet hose from the fuel filter.
CAUTION:
wPut a suitable container or shop towel under the fuel filter.
wSlowly loosen the union bolt.
(d) Install the fuel inlet hose and SST (pressure gauge) to the
fuel filter with the 3 gaskets and SST (union bolt).
SST 09268±45012
Torque: 29 NVm (300 kgfVcm, 22 ftVlbf)
(e) Wipe off any splattered gasoline.
(f) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020 EG±264
± ENGINESFI SYSTEM (2JZ±GTE)

(g) Reconnect the negative (±) terminal cable to the battery.
(h) Turn the ignition switch ON.
(i) Measure the fuel pressure.
Fuel pressure:
226±275 kPa (2.3±2.8 kgf/cm
2, 33±40 psi)
If pressure is high, replace the fuel pressure regulator.
If pressure is low, check the following parts:
wFuel hoses and connections
wFuel pump
wFuel filter
wFuel pressure regulator
(j) Remove the SST from the DLC1.
SST 09843±18020
(k) Start the engine.
(l) Disconnect the vacuum sensing hose from the fuel pressure
regulator, and plug the hose end.
(m) Measure the fuel pressure at idle.
Fuel pressure:
226±275 kPa (2.3±2.8 kgf/cm
2, 33±40 psi)
(n) Reconnect the vacuum sensing hose to the fuel pressure
regulator.
(o) Measure the fuel pressure at idle.
Fuel pressure:
167±216 kPa (1.7±2.2 kgf/cm
2, 24±31 psi)
If pressure is not as specified, check the vacuum sensing
hose and fuel pressure regulator.
(p) Stop the engine.
(q) Check that the fuel pressure remains as specified for 5
minutes after the engine has stopped.
Fuel pressure:
147 kPa (1.5 kgf/cm
2, 21 psi) or more
If pressure is not as specified, check the fuel pump, pressure
regulator and/or injectors.
(r) After checking fuel pressure, disconnect the negative (±)
terminal cable from the battery and carefully remove the SST
to prevent gasoline from splashing.
SST 09268±45012
(s) Reinstall the fuel inlet hose to the fuel filter with 2 new gaskets
and the union bolt.
Torque: 29 NVm (300 kgfVcm, 22 ftVlbf)
(t) Reconnect the negative (±) terminal cable to the battery.
(u) Check for fuel leaks.
(See item 5 in fuel system in precaution)
± ENGINESFI SYSTEM (2JZ±GTE)EG±265

COMPONENTS FOR REMOVAL AND
INSTALLATION
FUEL PUMP REMOVAL
CAUTION: Do not smoke or work near an open flame when
working on the fuel pump.
1. TAKE OUT FLOOR CARPET
2. REMOVE SPARE WHEEL COVER
3. REMOVE SPARE WHEEL
4. REMOVE SERVICE HOLE COVER EG±266
± ENGINESFI SYSTEM (2JZ±GTE)

5. REMOVE FUEL PUMP AND SENDER GAUGE ASSEMBLY
(a) Disconnect the connector and hoses from the fuel pump
bracket:
(1) Fuel pump connector
(2) Fuel outlet hose
Remove the union bolt and 2 gaskets, and disconnect
the outlet hose.
(3) Fuel return hose
(4) Fuel breather hose
(b) Remove the retainer clamp.
(c) Using SST, loosen the retainer.
SST 09808±14010
(d) Remove the retainer, and disconnect the fuel pump and
sender gauge assembly from the fuel tank.
(e) Disconnect the fuel return hose from the return port of the fuel
pump bracket.
(f) Remove the fuel pump, sender gauge assembly and gasket.
FUEL PUMP INSPECTION
1. INSPECT FUEL PUMP RESISTANCE
Using an ohmmeter, measure the resistance between termi-
nals 4 and 5.
Resistance:
0.1±3.0
at 20°C (68°F)
If the resistance is not as specified, replace the fuel pump,
lead wire or fuel pump bracket.
2. INSPECT FUEL PUMP OPERATION
Connect a tester lead from terminal 4 of the connector to the
positive (+) terminal of the battery; connect another tester
lead from terminal 5 of the connector to the negative (±) termi-
nal of the battery.
NOTICE:
wThese tests must be performed quickly (within 10 se-
conds) to prevent the coil from burning out.
± ENGINESFI SYSTEM (2JZ±GTE)EG±267

wKeep the fuel pump as far away from the battery as pos-
sible.
wAlways connect or disconnect at the battery.
If operation is not as specified, replace the fuel pump, lead
wire or fuel pump bracket.
COMPONENTS FOR DISASSEMBLY AND
ASSEMBLY
FUEL PUMP DISASSEMBLY
Assembly is in the reverse order of disassembly.
1. REMOVE FUEL SENDER GAUGE FROM FUEL PUMP
BRACKET
(a) Disconnect the connector from the fuel pump bracket.
(b) Remove the 2 screws and sender gauge. EG±268
± ENGINESFI SYSTEM (2JZ±GTE)

2. REMOVE FUEL PUMP FROM PUMP BRACKET
(a) Remove the 2 nuts and spring washers, and disconnect the
lead wire from the fuel pump.
(b) Disconnect the connector from the fuel pump bracket, and
remove the lead wire.
(c) Pull out the lower side of the fuel pump from the pump
bracket.
(d) Remove the rubber cushion from the fuel pump.
(e) Disconnect the fuel hose from the fuel pump, and remove the
fuel pump.
3. REMOVE FUEL PUMP FILTER FROM FUEL PUMP
(a) Using a small screwdriver, remove the clip.
INSTALLATION HINT: Use a new clip.
(b) Pull out the pump filter.
FUEL PUMP INSTALLATION
1. INSTALL FUEL PUMP AND SENDER GAUGE ASSEMBLY
(a) Install a new gasket to the fuel tank.
(b) Insert fuel pump and sender gauge assembly into the fuel
tank.
(c) Connect the fuel return hose to the return port of the fuel
pump bracket.
(d) Align the arrow marks of the fuel pump bracket and fuel tank.
± ENGINESFI SYSTEM (2JZ±GTE)EG±269

(e) Temporarily install the retainer.
(f) Using SST, tighten the retainer until the arrow mark on
retainer is within the lines on the fuel tank.
SST 09808±14010
(g) Check that the arrow marks of the fuel pump bracket and fuel
tank are aligned.
(h) Install the retainer clamp.
(i) Connect the connector and hoses to the fuel pump bracket:
wFuel pump connector
wFuel outlet hose
Connect the outlet hose with 2 new gaskets and the union
bolt.
Torque: 29 NVm (300 kgfVcm, 22 ftVlbf)
wFuel return hose
wFuel breather hose
2. INSTALL SERVICE HOLE COVER
3. INSTALL SPARE WHEEL
4. INSTALL SPARE WHEEL COVER
5. INSTALL FLOOR CARPET
6. CHECK FOR FUEL LEAKS
(See item 5 in fuel system in precaution) EG±270
± ENGINESFI SYSTEM (2JZ±GTE)