1995 TOYOTA SUPRA engine

(See page EG±20)
Check idle speed.
Proceed to matrix chart of problem symp-
toms on page EG±514.
(1) Shift transmission into ªNº position.
(2) Warm up engine to normal operating tempera±
ture.
(3) Switch OFF all accessories.
(4) Switch OFF air conditioning.
(5) Connect tachometer test probe to terminal
IG of data link connector 1.
Check Idle speed.
Idle speed: 650  50 rpm

Never allow tachometer test probe to touch
ground as it could result in damage to igniter
and/or ignition coil.

As some tachometers are not compatible
with this ignition system, we recommended
that you confirm the compatibility of your
unit before use.
Check ignition timing.
(1) Shift transmission into ªNº position.
(2) Warm up engine to normal operating tempera±
ture.
(3) Keep the engine speed at idle.
(4) Using SST, connect terminals TE1 and E1 of
data link connector 1.
SST 09843±18020
(5) Connect a timing light clip to the check wire.
(See page EG±20)
Check ignition timing.
Ignition timing: 10 2° BTDC @ idle
Proceed to matrix chart of problem symp-
toms on page EG±514.
Proceed to page EG±518 and continue to
troubleshoot.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±507

(See page
IG±26)
Check fuel pressure.
Proceed to page EG±264 and continue to
troubleshoot.
(1) Be sure that there is enough fuel in the tank.
(2) Turn ignition switch ON.
(3) Using SST, connect terminals FP and +B of
data link connector 1.
SST 09843±18020
Check that there is pressure in the hose from the fuel
filter.
If there is fuel pressure, you will hear the sound of fuel
flowing.
Never make a mistake with the terminal con-
nection position as this will cause a malfunc-
tion.
Check for spark.
Proceed to page IG±21 and continue to trou-
bleshoot.
Proceed to matrix chart of problem symptoms
on page EG±514.
(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 the injectors
during this test, don't crank the engine for more than 1
Ð 2 seconds at a time.
EG±508± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

PARTS LOCATION
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±509

STANDARD VALUE OF ECM TERMINALS
Connectors of the engine control module are waterproof and are
the bolt type.
For waterproof type connectors, in order to measure the voltage
of ECM terminals and the resistance of connected parts, connect
the inspection sub wire harness between the ECM and vehicle
wire harness, then do the inspection.
The inspection method of inserting a tester probe from the other
side of connector significantly reduces the waterproof perfor-
mance.
Disconnect the connector by fully loosening the bolt.
PREPARATION
1. Turn the ignition switch OFF.
2. Turn up the passenger side floor carpet.
(See page EG±324)
3. Remove the ECM protector.
4. Disconnect the connector from the ECM.
After completely loosening the bolt, the 2 parts of the connec-
tor can be separated.
NOTICE:
wDo not pull the wire harness when disconnecting the con-
nector.
wWhen disconnecting the connector, the ECM's back±up
power source is cut off, so the malfunction codes, etc. re-
corded in the ECM memory are cancelled.
wNever insert a tester probe or male terminal used for in-
spection purposes into the female terminal of the vehicle
wire harness. Otherwise, the female terminal may be wid-
ened, which can result in faulty connection.
5. Connect SST (check harness ºAº) between the ECM and
connector of the vehicle wire harness.
SST 09990±01000
HINT: The arrangement of the check connector terminals are
the same as those of the ECM.
See page EG±511.
6. Disconnect the SST.
SST 09990±01000
7. Reconnect the connector to the ECM.
(a) M a t c h t h e m a l e connector correctly with the female
connector, then press them together.
(b) Tighten the bolt.
Make sure the connector is completely connected by tighten-
ing the bolt until there is a clearance of less than 1 mm (0.04
in.) between the bottom of the male connector and the end
of the female connector.
8. Install the ECM protector and floor carpet. EG±510
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

STANDARD VALUE OF ECM TERMINALS
Always
IG switch ON
IG switch ON
IG switch ON and apply vacuum to the
throttle opener Throttle valve fully closed
IG switch ON
Main or sub±throttle valve fully closed
Idling, Intake air temp. 0°C (32°F) to 80°C
(176°F)
IG switch ON Throttle valve fully open
IG switch ON Sub±throttle valve fully closed
IG switch ON
Main or sub±throttle valve fully closed
IG switch ON Sub±throttle valve fully open
IG switch ON
Main or sub±throttle valve fully open
Idling, Engine coolant temp. 60°C (140°F) to
120°C (248°F)
Cranking
IG switch ON
Idling
IG switch ON
IG switch ON
Idling
Idling
Idling
Idling
Idling
IG switch ON
IG switch ON
IG switch ON
Pulse generation
Pulse generation
Pulse generation
Pulse generation
Pulse generation
Symbols (Terminals No.)STD Voltage (V)Condition
(See page EG±583)
(See page EG±521)
(See page EG±521)
(See page EG±517)
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±511

 Symbols (Terminals No.) STD Voltage (V) Condition
 EGR (B75) E01 (B80) Below 2.0 Idling
 EGR (B75)±E01 (B80) 9 ~ 14 Engine speed at 3,500 rpm
 VG (B66)±E21 (B28) 0.7 ~ 1.7 Idling
 
 
ISC1 (B35), ISC2 (B34)
Ð E01 (B80)
ISC3 (B33), ISC4 (B32) 
 
Pulse generation
(See page EG±586) 
 Idling when A/C switch ON or OFF
 
VF1 (B29)±E1 (B69) 

1.8 ~ 3.2 

Maintain engine speed at 2,500 rpm for 2
minutes after warming up then return to Idling
 
 OX1 (B48), OX2 (B47)±E1 (B69)
 
 Pulse generation
(See page EG±529)
 
 Maintain engine speed at 2,500 rpm for 2
minutes after warming up
 
HT1 (B71) HT2 (B72) E01 (B80)
 Below 3.0 Idling HT1 (B71), HT2 (B72)±E01 (B80) 9 ~ 14 IG switch ON 
 KNK1 (B50), KNK2 (B49)±E1 (B69)
 
 Pulse generation
(See page EG±563) 
 Idling
 
 
NSW (B76) E1 (B69)
 
 9 ~ 14
 
 IG switch ON
Other shift position in ºPº, ºNº position
 
 
NSW (B76)±E1 (B69) 
 0 ~ 3.0
 
 IG switch ON
Shift position in ºPº, ºNº position
 
 SP1 (A2)±E1 (B69)
 
 
Pulse generation
(See page EG±556) 
 
IG switch ON
Rotate driving wheel slowly
 TE1 (A20)±E1 (B69) 9 ~ 14 IG switch ON
 TE2 (A19)±E1 (B69) 9 ~ 14 IG switch ON
 W (A6)±E1 (B69) 9 ~ 14 Idling
  0 ~ 3.0 IG switch ON
 OD1 (A12)±E1 (B69) 9 ~ 14 IG switch ON
 A/C (A34)±E1 (B69) 7.5 ~14 A/C switch OFF
  0 ~ 1.5 A/C switch ON (At idling)
 ACMG (A23)±E1 (B69) 0 ~ 3.0 A/C switch ON (At idling)
  9 ~ 14 A/C switch OFF
 FPU (B73)±E01 (B80) 9 ~ 14 IG switch ON
  Below 2.0 Restarting at high engine coolant temp.
 ELS (A15)±E1 (B69) 7.5 ~ 14 Defogger switch and taillight switch ON
  0 ~ 1.5 Defogger's switch and taillight switch OFF
 VSV1 (B40)±E1 (B69) Below 3.0 Immediately after racing
  9 ~ 14 Idling
 VSV2 (B39)±E1 (B69) Below 3.0 For 2 sec. after IG switch ON to OFF
  9 ~ 14 Idling
 VSV3 (B38)±E1 (B69) 9 ~ 14 Idling
 
 
 PMC (B60)±E1 (B69)
 
 
 
Below 3.0
 
 
 
Idling (for M/T)
Idling and shift position ºPº, ºNº position
(for AT)
 

PMC (B60)±E1 (B69)
 

9 ~ 14 

Idling and other shift position ºPº, ºNº
position (for A/T))
 
PM1 (B62)±E2 (A65)
 
2.3 ~ 3.0
 
IG switch ON 
 
 
 1.8 ~ 2.4
 
 IG switch ON and apply vacuum 26.7 kPa
(200 mmHg, 7.9 in Hg)
EG±512± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

REFERENCE VALUE OF ECM DATA
HINT: ECM data can be monitored by TOYOTA hand±held
tester.
1. Hook up the TOYOTA hand±held tester to DLC2.
2. Monitor ECM data by following the prompts on the tester
screen.
Please refer to the TOYOTA hand±held tester operator's manual
for further details.
REFERENCE VALUE 
 Item
 
 Inspection condition
 
 Reference value
 
 INJECTOR 
 
Engine cold to hot
Engine idling at normal operating temp.*1
 
 
Gradually decreases
Approx. 1.8 msec.
 IGNITION Increase engine speed Gradually increases
 
 
 
 
IAC STEP #
 
 
 
 
Engine idling at normal operating temp..*1
A/C switch ON
A/T shifting in ºDº position
Ignition switch ON (Engine off)
 
 
 
 
20 ~ 30 steps
Step increases
Step increases
Approx. 125 steps`
 ENGINE SPEED RPM kept stable (Comparison with tachometer) No great changes
 
 MAF
 
 Engine idling at normal operating temp..*1
Increase engine speed
 
 Approx. 3.8 g/s
Gradually increases
 ECT Engine at normal operating temp. 75±95°C (185±203°F).*2 
 
 THROTTLE
 
 
 
Closed throttle position
Wide open throttle
From closed throttle position to wide open throttle
 
 
 
Below 5°
Above 70°
Gradually increases 
 
 
VEHICLE SPD
 
 
 
During driving
(Comparison with speedometer)
 
 
 
No large differences
 TARGET A/FL Engine idling at normal operating temp. 2.50 + 1.25 V*3
 A/F FB LEFT RPM stable at 2,500 rpm with normal operating temp. ON
 KNOCK FB Depress throttle pedal suddenly during idling ON 
 STA SIGNAL 
 During cranking 
 ON
 CTP SIGNAL Closed throttle position ON
 A/C SIGNAL A/C switch ON ON
 
 PNP SIGNAL.*4 
 
When shifting from ºPº or ºNº position into a position
other than ºPº or ºNº 
 GEAR
 OxL RPM stable at 2,500 rpm with normal operating temp. RICH LEAN is repeated
*1: All accessories and A/C switched OFF
*
2: If the engine coolant temp. sensor circuit is open or shorted, the ECM assumes an engine coolant temp.
value of 80°C (176°F).
*
3: When feedback control is forbidden, 0 V is displayed.
*
4: A/T only
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±513

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