1986 TOYOTA SUPRA check engine

(See page EG±404)
(See page EG±230)
Check voltage between terminal ACIS of engine control module connector
and body ground.
(1) Connect SST (check harness ªAº).
(See page EG±404)
SST 09990±01000
(2) Turn ignition switch ON.
Measure voltage between terminal ACIS of en-
gine control module connector and body ground.
Voltage: 9 Ð 14 V
Check for vacuum tank. (See page EG±230)
Repair or replace harness or connector.
Check and replace engine control module.
Check for open and short in harness and connector between EFI main relay
and engine control module (See page
IN±30).
EG±480± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

INSPECTION PROCEDURE
Check VSV for fuel pressure control.
(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 39
at 20°C (68°F)
(2) Resistance: 1 M
or higher
Check operation of VSV when battery positive
voltage is applied and released to the VSV termi-
nals.
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.
Replace VSV for fuel pressure control. EG±482
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

(See page EG±404)
Check voltage between terminal FPU of engine control module connector
and body ground.
(1) Connect SST (check harness ªAº).
(See page EG±404)
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
Proceed to next circuit inspection shown on
matrix chart (See page EG±408).
Repair or replace harness or connector.
Check and replace engine control module.
Check for open and short in harness and connector between engine control
module and VSV, VSV and EFI main relay (See page
IN±30).
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING7EG±483

Check voltage between terminals TE1, TE2 and E1 of data link connectors
1 and 2.
Turn ignition switch ON.
(1) For DLC1, measure voltage between terminal
TE1 and E1.
(2) For DLC2, measure voltage between terminals
TE1, TE2 nd E1.
Voltage: 9 Ð 14 V
Check and replace engine control module.
Check continuity between terminal E1 of data link connectors1, 2 and body
ground.
Repair or replace harness or connector.
Check and replace engine control module.
Check for open and short in harness and connector between engine control
module and data link connectors1, 2 (See page
IN±30).
Repair or replace harness or connector.
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±GE ENGINE TROUBLESHOOTINGEG±485

SFI SYSTEM (2JZ±GTE)
PREPARATION
SST (SPECIAL SERVICE TOOLS)
09205±76030 Cylinder Head Setting Bolt
Tightening Adaptor
09268±41045Injection Measuring Tool Set
(09268±41070)No.4 Union
(90405±09015)No.1 Union
09268±45012 EFI Fuel Pressure Gauge
ECT sensor
09612±24014 Steering Gear Housing Overhaul
Tool Set
(09617±24011) Steering Rack Wrench
09631±22020 Power Steering Hose Nut
14 x 17 mm Wrench Set
09808±14010Fuel Sender Gauge Tool Assy
09816±30010 Oil Pressure Switch Socket
09842±30080 Wiring ªEº EFI Inspection
Knock sensor
Fuel pressure pulsation damper
09843±18020 Diagnosis Check Wire
Injector
Fuel line flare nut
EG±258± ENGINESFI SYSTEM (2JZ±GTE)

09990±01000Engine Control Computer Check
Harness ªAº
RECOMMENDED TOOLS
09082±00050 TOYOTA Electrical Tester Set
09200±00010Engine Adjust Kit
09258±00030 Hose Plug SetPlug for vacuum hose, fuel
hose etc.
EQUIPMENT
 
 Carburetor cleaner
 
 
 
 Graduated cylinder 
 Injector
 
 
Soft brush 
 
 
 
Sound scope 
 
Injector
 Tachometer 
 
 Torque wrench
 
 
 
 Vacuum gauge 
 
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
± ENGINESFI SYSTEM (2JZ±GTE)EG±259

PRECAUTION
1. Before working on the fuel system, disconnect the
negative (±) terminal cable from the battery.
HINT: Any diagnostic trouble code retained by the computer
will be erased when the negative (±) terminal cable is discon-
nected.
Therefore, if necessary, read the diagnosis before discon-
necting the negative (±) terminal cable from the battery.
2. Do not smoke or work near an open flame when working
on the fuel system.
3. Keep gasoline away from rubber or leather parts.
MAINTENANCE PRECAUTIONS
1. PRECAUTION WHEN CONNECTING GAUGE
(a) Use ba tte ry as th e po we r so u rce fo r th e timin g lig h t,
tachometer, etc.
(b) Connect the tester probe of a tachometer to the terminal IG

of the DLC1.
2. IN EVENT OF ENGINE MISFIRE, FOLLOWING
PRECAUTIONS SHOULD BE TAKEN
(a) Check proper connection of battery terminals, etc.
(b) After repair work, check that the ignition coil terminals and all
other ignition system lines are reconnected securely.
(c) When cleaning the engine compartment, be especially
careful to protect the electrical system from water.
3. PRECAUTIONS WHEN HANDLING OXYGEN SENSOR
(a) Do not allow oxygen sensor to drop or hit against an object.
(b) Do not allow the sensor to come into contact with water. EG±260
± ENGINESFI SYSTEM (2JZ±GTE)

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