1995 TOYOTA SUPRA engine oil

Suspect area
See page
Symptom
Engine does not crank
No initial combustion
No complete combustion
Engine cranks normally
Cold engine
Hot engine
Incorrect first idle
High engine idle speed
Low engine idle speed
Rough idling
Hunting
Hesitation/Poor acceleration
Muffler explosion (after fire)
Surging
Soon after starting
After accelerator pedal depressed
After accelerator pedal released
During A/C operation
When shifting N to D
Does not
start
Difficult to
start
Poor Idling
Engine Stall
Poor
Driveability
Back up power source circuitECM power source circuitPark/neutral position switch circuitSwitch condition signal circuitEGR systemStarter signal circuitMass air flow meter circuitInjector circuitIAC valve circuitFuel pump control circuitA/C signal circuit (Compressor circuit)Turbo control circuitVSV circuit for fuel Pressure ControlCompressionSpark plugIgnition signal circuit (Spark test)Starter and Starter relayIgnition coilEngine control module (ECM)Theft deterrent ECUA/T faulty
EG±544EG±559EG±564EG±571EG±574EG±576EG±581EG±583EG±586EG±568EG±595EG±589AC±62ST±3
,
12
IG±21IG±23IG±22EG±9AT2±101BE±123IN±35
MATRIX CHART OF PROBLEM SYMPTOMS
When the malfunction code is not confirmed in the diagnostic trouble code check and the problem still can not
be confirmed in the basic inspection, proceed to this matrix chart and troubleshoot according to the numbered
order given below. EG±514
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

CIRCUIT DESCRIPTION
Camshaft position sensors (G1 and G2 signals) are mounted on the intake side of the cylinder head
and the crankshaft position sensor (NE signal) is mounted on the oil pump body. These sensors consist
of a timing rotor and pick up coil.
The G1, G2 timing rotors have 1 tooth each on their outer circumference and are mounted on the intake
camshaft.
When the intake camshaft rotates, the protrusion on the timing rotors and the air gap on the pick up
coil change, causing fluctions in the magnetic field and generating an electromotive force in the pick
up coil.
The NE timing rotor has 12 teeth and is mounted on the crankshaft. The NE signal sensor generates
12 NE signals per engine revolution. The ECM detects the standard crankshaft angle based on the G1,
G2 signals, and the actual crankshaft angle and the engine speed by the NE signals.
DTC No.Diagnostic Trouble Code Detecting ConditionTrouble Area
No ªNEº or ªG1º and ªG2º signal to ECM for 2 sec.
or more after cranking

Open or short in crankshaft position
sensor, camshaft position sensor No.1, No.2
circuit

Crankshaft position sensor

Camshaft position sensor No.1, No.2

Starter

ECM
CIRCUIT INSPECTION
DTC 12 G NE Signal Circuit (No.1)
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±515

DTC 14 Ignition Signal Circuit
CIRCUIT DESCRIPTION
The ECM determines the ignition timing, turns on Tr1 at a predetermined angle (°CA) before the desired ignition
timing and outputs an ignition signal (IGT) º1º to the igniter.
Since the width of the IGT signal is constant, the dwell angle control circuit in the igniter determines the time
the control circuit starts primary current flow to the ignition coil based on the engine rpm and ignition timing one
revolution ago, that is, the time the Tr
2 turns on.
When it reaches the ignition timing, the ECM turns Tr
1 off and outputs the IGT signal ºOº.
This turns Tr
2 off, interrupting the primary current flow and generating a high voltage in the secondary coil which
causes the spark plug to spark. Also, by the counter electromotive force generated when the primary current
is interrupted, the igniter sends an ignition confirmation signal (IGF) to the ECM.
The ECM stops fuel injection as a fail safe function when the IGF signal is not input to the ECM.
 DTC No. Diagnostic Trouble Code Detecting Condition Trouble Area 
 
 
 
14
 
 
 
 
No IGF signal to ECM for 4 ~ 7 consecutive
IGT signals with engine speed less than
3,000 rpm
 
 
 
 

Open or short in IGF circuit from igniter to
ECM

Igniter

ECM
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±519

Check for spark.
(1) Remove ignition coil. (See page IG±26)
(2) Remove spark plug.
(3) Install the spark plug to the ignition coil, and connect
the ignition coil connector.
(4) Ground the spark plug.
Check if spark occurs while engine is being cranked.
To prevent excess fuel being injected from injectors dur-
ing this test, don't crank the engine for more than 1Ð2
seconds at a time.
Check for open and short in harness and connector in IGF signal circuit
between engine control module and igniter (See page IN±30).
Repair or replace harness or connector.
Replace igniter.
Check and replace engine control module.
Disconnect igniter connector and check voltage between terminal IGF of
engine control module connector and body ground.
(1) Disconnect igniter connector.
(2) Connect SST (check harness ªAº).
(See page EG±510)
SST 09990±01000
(3) Turn ignition switch ON.
Measure voltage between terminal IGF of engine con-
trol module connector and body ground.
Voltage: 4.5 Ð 5.5 V
INSPECTION PROCEDURE
EG±520± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

Check for open and short in harness and connector between ignition
switch and ignition coil, ignition coil and igniter (See page IN±30).
Disconnect ignition coil connector.
(See page IG±23)
Measure resistance between terminals of ignition coil
connector.
Repair or replace harness or connector.
Check ignition coil.
ªColdº is from Ð 10°C (14°F) to 50°C (122°F) and ªHotº is
from 50°C (122°F) to 100°C (212°F).
Replace ignition coil.
Replace igniter.
EG±522± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

ECM Power Source Circuit
CIRCUIT DESCRIPTION
When the ignition switch is turned on, battery volt-
age is applied to the terminal IGSW of the ECM,
and the main relay control circuit in the ECM sends
a signal to the terminal M±REL of the ECM, switch-
ing on the main relay. This signal causes current to
flow to the coil, closing the contacts of the main
relay and supplying power to the terminal + B of the
ECM.
If the ignition switch is turned off, the ECM contin-
ues to switch on the main relay for a maximum of
2 seconds for the initial setting of the IAC valve. EG±576
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

CIRCUIT DESCRIPTION
The IAC valve is situated on the intake air chamber In-
take air bypassing the throttle valve is directed to the
IAC valve through a passage.
A step motor is built into the IAC valve. It consists of 4
coils, a magnetic rotor, valve shaft and a valve.
When the current flows to the coils due to signals from
the ECM, the rotor turns and moves the valve shaft for-
ward or backward, changing the clearance between
the valve and the valve seat.
In this way the intake air volume bypassing the throttle
valve is regulated, controlling the engine speed.
There are 125 possible positions to which the valve can
be opened.

With the engine idling measure wave forms
between terminals ISC1, ISC2, ISC3,
ISC4 and E01 of engine control module
when A/C switch ON or OFF.
HINT:
The correct waveforms are as shown.
INSPECTION USING OSCILLOSCOPEReference
IAC Valve Circuit
EG±586± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

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