heater TOYOTA SUPRA 1986 Service Repair Manual

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)

13. DISCONNECT ENGINE WIRE PROTECTOR FROM BODY
Remove the 2 bolts, and disconnect the wire protector from
the body.
14. DISCONNECT HOSES
Disconnect these hoses:
(1) Heater hose from No.3 water bypass pipe
(2) EVAP hose from No.1 vacuum pipe
15. DISCONNECT IAC VALVE PIPE FROM NO.2 AIR TUBE
(a) Disconnect the engine wire from the clamp.
(b) Disconnect these hoses:
(1) Air hose (from No.1 vacuum pipe) from IAC valve pipe
(2) Air hose from No.2 air tube
(c) Disconnect the IAC valve pipe from the clamp.
16. DISCONNECT NO.1 VACUUM PIPE FROM AIR TUBES
(a) Disconnect these connectors:
(1) VSV connector for intake air control valve
(2) VSV connector for exhaust bypass valve
(b) Disconnect the engine wire from the 3 clamps.
(c) Disconnect these hoses:
(1) Air hose from No.4 air tube
(2) Air hose from No.1 air tube
(3) Air hose (from VSV for waste gate valve) from vacuum
pipe
(4) Air hose (from VSV for exhaust gas control valve) from
vacuum pipe
(5) Vacuum hose (from air bypass valve) from No.1 air tube
(6) 2 air hoses (from VSV for exhaust bypass valve) from
vacuum pipe
(7) Air hose (from No.2 air tube) from vacuum pipe
(8) Air hose from VSV for intake air control valve
(9) 2 air hoses (from pressure tank) from vacuum pipe
(d) Remove the 3 bolts, and disconnect the vacuum pipe from
the air tubes. EG±152
± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)

(b) Remove the 2 nuts, and disconnect the turbo oil pipe from
turbocharger. Remove the gasket.
INSTALLATION HINT:
wUse a new gasket.
wAlign the oil holes of the gasket and turbocharger
housing.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
(c) Disconnect the turbo oil hose from the turbo oil outlet on the
No.1 oil pan, and remove the turbo oil pipe.
29. REMOVE TURBOCHARGERS AND TURBINE OUTLET
ELBOW ASSEMBLY
(a) Disconnect these hoses:
(1) Heater hose (from No.3 water bypass pipe) from No.2
water bypass pipe
(2) Water bypass hose (from No.2 turbo water pipe) from
No.2 water bypass pipe
(b) Remove the 8 nuts holding the turbochargers to the exhaust
manifold.
INSTALLATION HINT:
wUse 8 new nuts.
wUniformly tighten the nuts in several passes.
Torque: 54 NVm (550 kgfVcm, 40 ftVlbf)
(c) Remove the 2 turbochargers and turbine outlet elbow
assembly.
(d) Remove the 2 gaskets.
INSTALLATION HINT: Use 2 new gaskets.
30. R E M O V E N O . 1 VACUUM PIPE FROM NO.2
TURBOCHARGER
Disconnect the 2 air hoses from the actuator for the exhaust
bypass valve, and remove the vacuum pipe.
31. REMOVE NO.2 AIR TUBE AND NO.3 WATER BYPASS
PIPE ASSEMBLY FROM NO.2 TURBOCHARGER
Remove the 2 bolts, the air tube, bypass pipe assembly and
gasket.
INSTALLATION HINT: Use a new gasket.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
EG±156± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
(1) Open or short in heater circuit of main heated oxygen
sensor (Fr) for 0.5 sec. or more.
(2) Main heated oxygen sensor (Fr) signal voltage is reduced to
between 0.35 V and 0.70 V for 90 sec. under conditions
Main Heated
Oxygen Sensor
Signal(a) ~ (d):
(2 trip dectection logic)*3
(a) Engine coolant temp.: Between 80°C (176°F) and
95°C (203°F)
(b) Engine speed: 1,500 rpm or more
(c) Load driving (Example A/T in Overdrive, (5th for
M/T), A/C ON, Flat road, 80 km/h (50 mph)
(d) Main heated oxygen sensor signal voltage:
Alternating above and below 0.45 V
Open or short in engine coolant temp. sensor circuit for 0.5
sec. or more
Open or short in intake air temp. sensor circuit for 0.5 sec.
or more
(1) Main heated oxygen sensor voltage is 0.45 V or less (lean)
for 90 sec. under conditions (a) and (b):
(2 trip dectection logic)*3
(a) Engine speed: 1,500 rpm or more
(b) Engine coolant temp.: 70°C or more
(a) Engine speed: Below 950 rpm
(b) Engine coolant temp.: 80°C (176°F) or more
(2 trip dectection logic)*4
(2) Engine speed varies by more than 20 rpm over the preced±
ing crank angle period during a period of 20 sec. or more
under conditions (a) and (b):
Intake Air
Temp. Sensor
Signal
Engine Coolant
Temp. Sensor
Circuit
Air±Fuel
Ratio Lean
Malfunction
*3: See page EG±503. EG±496
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 

Open or short in heater circuit of main heated oxygen
sensor

Main heated oxygen sensor heater

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 
 
 
 
 
 
 
 
 
Main heated oxygen sensor circuit
Mi h td
 
 
 
 ON
 
 
 
 ON
 
 
 
 

 
 
 
 
EG±525

Main heated oxygen sensor
ON

ON
 Main heated oxygen sensor    
     
     
 
 
 

Open or short in engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±530
 
 
 

Open or short in intake air temp. sensor circuit

Intake air temp. sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±532
 
Open or short in Main heated oxygen sensor circuit    
 Oen or short in Main heated oxygen sensor circuit

Main heated oxygen sensor    
 Main heated oxygen sensor

Ignition system    
 
gy

ECM    
 
Open or short in injector circuit    
 
Oen or short in injector circuit

Fuel linepressure (injector leak blockage) ON ON  EG 534

Fuel line pressure (injector leak, blockage)

Mechanical system malfunction (skipping teeth ofONONEG±534 
Mechanical system malfunction (skipping teeth of
timing belt)    
 timing belt)

Ignition system
    
 
Ignition system

Compression pressure (foreign object caught in valve)
    
 
Compression pressure (foreign object caught in valve)
M i fl t (i itk)    
 
Mass air flow meter (air intake)
ECM    

ECM
*1, 2: See page EG±502
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±497

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
(a) Engine speed: Below 950 rpm
(b) Engine coolant temp.: 80°C (176°F) or more
(2 trip dectection logic)*3
Engine speed varies by more than 20 rpm over the preceding
crank angle period during a period of 25 sec. or more
under conditions (a) and (b):
(1) Open or short in heater circuit of sub heated oxygen sensor
for 0.5 sec. or more
(2) Main heated oxygen sensor signal is 0.45 V or more and
sub heated oxygen sensor signal is 0.45 V or less under
conditions (a) ~ (c):
(2 trip dectection logic)*3
(a) Engine coolant temp.: 80°C (176°F) or more
(b) Engine speed: 1,5000 rpm or more
(c) Accel. pedal: Fully depressed for 2 sec. or more
Open or short in mass air flow meter circuit for 3 sec. or more
with engine speed less than 3,000 rpm
Open or short in turbo pressure sensor circuit for 0.5 sec. or
more
Open or short in BARO sensor circuit for 0.5 sec. or more
Sub Heated
Oxygen Sensor
Signal
Air±Fuel
Ratio Rich
Malfunction
Mass Air Flow
Meter Circuit
Turbo Pressure
Malfunction
Turbo Pressure
Sensor Circuit
Barometric
Pressure
Sensor Circuit
(c) Engine speed: 2,4000 rpm or more
(a) Mainfold absolute pressure: 200 kPa (2.0 kgf/cm2,
29 psi) or more
(b) Thottle valve opening angle: 20° or more
All conditions below are detected continuously for 2 sec. or more:
*3: See page EG±503. EG±498
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 
 
 
 
 

Open or short in injector circuit

Fuel line pressure (injector leak, blockage)

Mechanical system malfunction (skipping teeth of
timing belt)

Ignition system

Compression pressure (foreign object caught in valve)

Mass air flow meter (air intake)

ECM
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
EG±534
 
 
 
 

Open or short in heater circuit of sub heated oxygen
sensor.

Sub heated oxygen sensor

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 
 
 
 
 
 
 
 
 
 

Open or short in sub heated oxygen sensor circuit

Sub heated oxygen sensor

ECM
 
 
 
 
 
ON
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
 
 
EG±540
 
 
 

Open or short in mass air flow meter circuit

Mass air flow meter

ECM
 
 
 ON
 
 
 N.A.
 
 
 
 
 
 EG±544
 
 
 
 
 

Actuator (for waste gate valve)

Short in VSV for waste gate valve circuit

ECM
 
 
 
 
 
ON
 
 
 
 
 
N.A.
 
 
 
 
 

 
 
 
 
 
EG±546
 
 
 

Open or short in turbo pressure sensor circuit

Turbo pressure sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±549
 
 
 

ECM
 
 
 
ON
 
 
 
ON
 
 
 
 
 
 
EG±549
*1, 2: See page EG±502.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±499

See page EG±503.
CIRCUIT DESCRIPTION
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three±way
catalytic converter is used, but for most efficient use of the three±way catalytic converter, the air±fuel
ratio must be precisely controlled so that it is always close to the stoichiometric air±fuel ratio.
The oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity
of the stoichiometric air±fuel ratio. This characteristic is used to detect the oxygen concentration in the
exhaust gas and provide feedback to the computer for control of the air±fuel ratio.
When the air±fuel ratio becomes LEAN, the oxygen concentration in the exhaust increases and the
oxygen sensor informs the ECM of the LEAN condition (small electromotive force: 0 V).
When the air±fuel ratio is RICHER than the stoichiometric air±fuel ratio the oxygen concentration in the
exhaust gas is reduced and the oxygen sensor informs the ECM of the RICH condition (large electro-
motive force: 1 V).
The ECm judges by the electromotive force from the oxygen sensor whether the air±fuel ratio if RICH
or LEAN and controls the injection duration accordingly. However, if malfunction of the oxygen sensor
causes an output of abnormal electromotive force, the ECM is unable to perform accurate air±fuel ratio
control.
The main heated oxygen sensor include a heater which heats the Zirconia element. The heater is con-
trolled by the ECM. When the intake air volume is low (the temperature of the exhaust has is low) current
flows to the heater to heat the sensor for accurate oxygen concentration detection.)
Diagnostic Trouble Code Detecting ConditionDTC No.Trouble Area
(1) Open or short in heater circuit of main heated
oxygen sensor for 0.5 sec. or more.
(2) Main heated oxygen sensor signal voltage is
reduced to be 0.35 V and 0.70V for 60 sec.
under condition (a) ~ (d):
(2 trip detection logic)*1
(a) Engine coolant temp.: Between 80°C
(176°F) and 95°C (203°F)
(b) Engine speed: 1,500 rpm or more
(c) Load driving (Example A/T in
overdrive (5th for M/T), A/C ON, Flat
road, 80 km/h (50 mph))
(d) Main heated oxygen sensor signal
voltage: Alternating above and below
0.45V

Open or short in heater circuit of main heated
oxygen sensor

Main heated oxygen sensor heater

ECM

Main heated oxygen sensor circuit

Main heated oxygen sensor
DTC 21 Main Heated Oxygen Sensor Circuit
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±525

Disconnect main heated oxygen sensor connector.
Measure resistance between terminals 1 and 2 of
main heated oxygen sensor connector.
Resistance: 11 Ð 16
at 20°C (68°F)
Check main heated oxygen sensor heater.
Replace main heated oxygen sensor.
Check and repair harness or connector between
main relay and main heated oxygen sensor, main
heated oxygen sensor and engine control module.
Warm up engine to normal operating temperature.
Measure voltage between terminals HT1 of engine
control module connector and body ground, when
engine is idling and racing at 4,000 rpm.
Check voltage between terminals HT1 of engine control module connector
and body ground.
Replace main heated oxygen sensor.*
Check and replace engine control module.
In the 4,000 rpm racing check, continue engine
racing at 4,000 rpm for approx. 20 seconds or
more.
*: It is probable the oxygen sensor has deteri±
orated. Usually, this cannot be confirmed by
visual inspection. EG±528
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page EG±9).
EG±261
IG±21
EG±568
EG±583
EG±530
EG±532
EG±544
EG±33
Check each circuit found to be a possible cause of trouble according to the results of the check in
Check each item found to be a possible cause of problem.
Check for open and short in harness and connector between engine
control module and main heated oxygen sensor, engine control module
and data link connector 1 (See page IN±30).
The numbers int he table below show the order in which the checks should be done.
Repair or replace harness or connector.
Repair or replace.
Replace main heated oxygen sensor.
Repair or replace.
Check and replace engine control module.
Check compression (See page EG±9).
Does malfunction disappear when a good main heated oxygen sensor is
installed?
Faulty sensor installation
Air leakage
Misfire
Fuel system
Injector circuit
Characteristics deviation
in engine coolant temp. sensor
Characteristics deviation
in intake air temp. sensor
Characteristics deviation in mass
air flow meter
Va l v e t i m i n g
Main heater oxygen sensor signal
continues at 0 V
EG±538± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING