TOYOTA SUPRA 1995 Service Repair Manual

(See page EG±510)
(See page IN±30).
(1) Connect SST (check harness ªAº).
(See page EG±510)
(2) Turn ignition switch ON.
Measure voltage between terminal VSV1, VSV2,
VSV3 of engine control module connector and
body ground.
Voltage: 9 Ð 14 V
Check voltage between terminal VSV1, VSV2, VSV3 of engine control
module connector and body ground.
Check actuator. (See page EG±144, 158)
Repair or replace harness or connector.
Check for open and short in harness and connector between EFI main replay
and engine control module (See page IN±30).
Check and replace engine control module. EG±594
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

VSV Circuit for Fuel Pressure Control
CIRCUIT DESCRIPTION
The ECM turns on a VSV (Vacuum Switching
Valve) to draw air into the diaphragm chamber
of the pressure regulator if it detects that the
temperature of the engine coolant is too high
during engine starting.
The air drawn into the chamber increases the
fuel pressure to prevent fuel vapor lock at high
engine temperature in order to help the en-
gine start when it is warm.
Fuel pressure control ends approx. 120 sec.
after the engine is started.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±595

INSPECTION PROCEDURE
(1) Remove VSV.
(2) Disconnect VSV connector.
(1) Measure resistance between terminals.
(2) Measure resistance between each terminal
and the body.
(1) Resistance: 33 Ð   at 20°C (68°F)
(2) Resistance: 1 M or higher
Check operation of VSV when battery positive volt-
age is applied and released to the VSV terminals.
Battery positive voltage is applied:
Air from port E is flowing out through the air fil-
ter.
Battery positive voltage is not applied:
Air from port E is flowing out through port G.
Check VSV for fuel pressure control.
Replace VSV for fuel pressure control.
EG±596± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page IN±30).
(1) Connect SST (check harness ªAº).
(See page EG±510)
SST 09990±01000
(2) Turn ignition switch ON.
Measure voltage between terminal FPU of engine
control module connector and body ground.
Voltage: 9 Ð 14 V
Check voltage between terminal FPU of engine control module
connector and body ground.
Proceed to next circuit inspection shown
on matrix chart (See page Eg±514).
Repair or replace harness or connector.
Check for open and short in harness and connector between engine control
module and VSV, VSV and EFI main relay (See page IN±30).
Check and replace engine control module.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±597

TE1 TE2 Terminal Circuit
CIRCUIT DESCRIPTION
Terminal TE1 is located in data link connectors 1 and 2. Terminal TE2 is located ONLY in data link connector
2.
The data link connector 1 is located in the engine compartment and the data link connector 2 is located in the
cabin. When these terminals are connected with the E1 terminal, diagnostic trouble codes in normal mode or
test mode can be read from the malfunction indicator lamp on the telltale light RH. EG±598
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page IN±30).
Turn ignition switch ON.
(1) For DLC1, measure voltage between terminal
TE1 and E1.
(2) For DLC2 measure voltage between terminals
TE1, TE2 and E1.
Voltage: 9 Ð 14 V
Check voltage between terminals TE1, TE2 and E1 of data link connectors
1 and 2.
Check and replace engine control module.
Repair or replace harness or connector.
Check for open and short in harness and connector between engine control
module and data link connectors 1, 2 (See page IN±30).
Repair or replace harness or connector.
Check and replace engine control module.
Check continuity between terminal E1 of data link connectors 1, 2 and
body ground.
INSPECTION PROCEDURE
HINT: If terminals TE1 and TE2 are connected with terminal E1, diagnostic trouble code is not output or test
mode is not activated.
Even though terminal TE1 is not connected with terminal E1, the malfunction indicator lamp blinks.
For the above phenomenon, the likely cause is an open or short in the wire harness, or malfunction inside
the ECM.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±599

TURBOCHARGER SYSTEM (2JZ±GTE)
PREPARATION
SST (SPECIAL SERVICE TOOLS)
09992±00241 Turbocharger Pressure Gauge
EQUIPMENT
 
 
Dial indicator 
 
Impeller wheel
 
 
Torque wrench 
 
COOLANT
 Item Capacity Classification
 
 Engine coolant (w/ Heater) M/T
A/T 
  9.5 liters (10.0 US qts. 8.4 lmp. qts)
9.4 liters (9.9 US qts, 8.3 lmp. qts) 
 Ethylene±glycol base
EG±140± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)

PRECAUTION
1. Do not stop the engine immediately after pulling a trailer
or after high speed or uphill driving. Idle the engine for
20±120 seconds, depending on how hard the vehicle has
been driven.
2. Avoid sudden acceleration or racing immediately after
starting a cold engine.
3. Do not run the engine with air cleaner removed, as this
may cause foreign material to enter and damage the
impeller wheel operating at high speed.
4. If a turbocharger is found to be defective and must be
replaced, check for the cause, and repair or replace the
following items as necessary:
wEngine oil level and quality
wConditions under which the turbocharger was used
wOil lines leading to the turbocharger
5. Use caution when removing and reinstalling the
turbocharger assembly. Do not drop it or knock it against
anything or grasp it by easily±deformed parts, such as
the actuator or rod, when moving it.
6. Use caution when removing and reinstalling the exhaust
gas control valve assembly. Do not drop it or knock it
against anything or grasp it by easily±deformed parts,
such as the actuator or rod, when moving it. The control
valve is ceramic.
7. Before removing the turbocharger, plug the intake and
exhaust ports and oil inlet to prevent entry of dirt or other
foreign material.
8. If replacing the turbocharger, check for accumulation of
sludge particles in the oil pipes, and if necessary,
replace the oil pipes.
9. Completely remove the gasket adhered to the lubrication
oil pipe flange and turbocharger oil flange.
10. Whe n re pla c ing bolt or nuts , us e only authorize d
replacement parts to prevent breakage or deformation.
11. If replacing the turbocharger, pour approx. 20 cm
3 (1.2 cu
in.) of fresh oil into the turbocharger oil inlet and turn the
impeller wheel by hand to spread oil to the bearing.
12. If overhauling or replacing the engine, cut the fuel supply
after reassembly and crank the engine for 30 seconds to
distribute oil throughout the engine. Then allow the
engine to idle for 60 seconds.
± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)EG±141

TROUBLESHOOTING
HINT: Before troubleshooting the turbocharger, first check the engine itself. (Valve clearance, engine com-
pression, ignition timing etc.)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
1. TURBOCHARGING PRESSURE TOO
LOW
2. RESTRICTED INTAKE SYSTEM
6. ERRATIC TURBOCHARGER
OPERATION
3. LEAK IN INTAKE AIR SYSTEM
4. RESTRICTED EXHAUST SYSTEM
5. LEAK IN EXHAUST SYSTEM
INSUFFICIENT ACCELERATION, LACK OF POWER OR EXCESSIVE FUEL
CONSUMPTION
(Possible Cause) Check Procedure and Correction Method)
Check turbocharging pressure. (See page EG±144)
Turbocharging pressure:
61±75 kPa
(062±0.76 kgf/cm
2,
8.8±10.8 psi)
If the pressure is below specifications, begin
diagnosis from item 2.
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check rotation of turbine shaft. If it does not
turn or turns with a heavy drag, replace the
turbocharger assembly.
Check axial and radial play of turbine shaft.
(See page EG±158)
Maximum axial play : 0.110 mm (0.0045 in.)
Maximum radial play : 0.162 mm (0.0064 in.)
If the play is greater than maximum, replace
the turbocharger assembly. EG±142
± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)

1. TURBOCHARGING HEAT INSULATOR
RESONANCE
2. EXHAUST PIPE LEAKING OR
VIBRATING
3. ERRATIC TURBOCHARGER
OPERATION
ABNORMAL NOISE
(Possible Cause) (Check Procedure and Correction Method)
Check for loose, improperly installed or deformed
insulator mounting bolts, and repair or replace as
necessary.
Check for deformed exhaust pipe, loose mounting
bolts or damaged gasket, and repair or replace as
necessary.
Refer to item 6 of INSUFFICIENT ACCELERATION,
LACK OF POWER OR EXCESSIVE FUEL
CONSUMPTION.
EXCESSIVE OIL CONSUMPTION OR WHITE EXHAUST
(Possible Cause) (Check Procedure and Correction Method)
FAULTY TURBOCHARGER SEALCheck for oil leakage in exhaust system.
wRemove the turbine elbow from the turbochar-
ger and check for excessive carbon deposits on
the turbine wheel. Excessive carbon deposits in-
dicate a faulty turbocharger.
Check for oil leakage in intake air system.
wCheck for axial and radial play of turbine shaft
and replace the turbocharger if necessary.
(See page EG±158)
Maximum axial play : 0.110 mm (0.0045 in.)
Maximum radial play : 0.162 mm (0.0064 in.)
NOTICE: Some oil mist in the blowby from the
PCV is normal.
Do not mistake it for an oil leak from the
turbocharger.
± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)EG±143