1986 TOYOTA SUPRA Service Repair Manual

EGR VACUUM MODULATOR
INSPECTION
1. DISCONNECT VACUUM HOSES FROM EGR VACUUM
MODULATOR
Disconnect the 2 vacuum hoses from ports P and Q of the
EGR vacuum modulator.
2. INSPECT EGR VACUUM MODULATOR OPERATION
(a) Block port P with your finger.
(b) Blow air into port Q, and check that the air passes through to
the air filter side freely.
(c) Start the engine, and maintain speed at 3,500 rpm.
(d) Repeat the above test. Check that there is a strong
resistance to air flow.
3. RECONNECT VACUUM HOSES TO EGR VACUUM
MODULATOR
Reconnect the 2 vacuum hoses to the proper locations.
EGR VALVE INSPECTION
1. REMOVE EGR PIPE
(a) Loosen the union nut of the EGR pipe.
(b) Remove the 2 bolts, EGR pipe and gasket.
2. REMOVE EGR GAS TEMPERATURE SENSOR
3. REMOVE EGR VALVE
(a) Disconnect these hoses from the EGR valve:
(1) Vacuum hose
(2) Pressure hose
(b) Remove the 2 nuts, EGR valve and gasket.
± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)EG±181

4. INSPECT EGR VALVE
Check for sticking and heavy carbon deposits.
If a problem is found, replace the EGR valve.
5. REINSTALL EGR VALVE
(a) Place a new gasket on the air intake chamber.
(b) Install the EGR valve with the 2 nuts.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
(c) Reconnect the following hoses to the EGR valve:
wVacuum hose
wPressure hose
6. REINSTALL EGR GAS TEMPERATURE SENSOR
Torque: 20 NVm (200 kgfVcm, 14 ftVlbf)
7. REINSTALL EGR PIPE
(a) Temporarily install the union nut of the EGR pipe.
(b) Install a new gasket and the EGR pipe with the 2 bolts.
Torque: 27 NVm (280 kgfVcm, 20 ftVlbf)
(c) Tighten the union nut of the EGR pipe.
Torque: 64 NVm (650 kgfVcm, 47 ftVlbf)
EG±182± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)

THREE±WAY CATALYTIC CONVERTER
(TWC) SYSTEM
EXHAUST PIPE ASSEMBLY INSPECTION
1. CHECK CONNECTIONS FOR LOOSENSESS OR
DAMAGE
2. CHECK CLAMPS FOR WEAKNESS, CRACKS OR
DAMAGE
TWC INSPECTION
CHECK FOR DENTS OR DAMAGE
If any part of the protector is damaged or dented to the extent
that it contacts the TWC, repair or replace it.
HEAT INSULATOR INSPECTION
1. CHECK HEAT INSULATOR FOR DAMAGE
2. CHECK FOR ADEQUATE CLEARANCE BETWEEN
CATALYTIC CONVERTER AND HEAT INSULATOR
± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)EG±183

COMPONENTS FOR FRONT TWC
REPLACEMENT
EG±184± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)

COMPONENTS FOR REAR TWC
REPLACEMENT
± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)EG±185

SERVICE SPECIFICATIONS
TORQUE SPECIFICATIONS
 Part tightened NVm kgfVcm ftVlbf
 EGR valve x Air Intake chamber 21 210 15
 EGR gas temperature sensor x EGR valve 20 200 14 
 EGR pipe x Cylinder head
 
 27
 
 280
 
 20
 EGR valve x EGR pipe 64 650 47
 No.2 front exhaust pipe (Front TWC) x Exhaust manifold 62 630 46
 Pipe support bracket x Transmission 43 440 32 
 No.2 front exhaust pipe (Front TWC) x Front exhaust pipe (Rear TWC) 
 43 
 440 
 32
 Front exhaust pipe (Rear TWC) x Center exhaust pipe 43 440 32
 Sub heated oxygen sensor x Front exhaust pipe 20 200 14
EG±186± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GTE)

EMISSION CONTROL SYSTEMS (2JZ±GE)
SYSTEM PURPOSE
The emission control systems are installed to reduce the amount of CO, HC and NOx exhausted from the
engine ((3), (4) and (5)), to prevent the atmospheric release of blow±by gas±containing HC (1) and evapo-
rated fuel containing HC being released from the fuel tank (2).
The function of each system is shown in the following table.
 System Abbreviation Function
 
 
 
 
 
 
(1) Positive Crankcase Ventilation
(2) Evaporative Emission Control
(3) Exhaust Gas Recirculation
(4) Three±Way Catalytic Converter
(5) Sequential Multiport Fuel Injection* 
 
 
 
 
 
PCV
EVAP
EGR
TWC
SFI 
 
 
 
 
 
Reduces HC
Reduces evaporated HC
Reduces NOx
Reduces CO, HC and NOx
Injects a precisely timed, optimum amount of fuel for re-
duced exhaust emissions
Remark: * For inspection and repair of the SFI system, refer to the SFI section this manual.
PREPARATION
RECOMMENDED TOOLS
09082±00050 TOYOTA Electrical Tester Set


EQUIPMENT
 
 Tachometer 
 
 
 Torque wrench 
 
 
 Vacuum gauge 
 
± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GE)EG±163

EMISSION CONTROL SYSTEMS (2JZ±GE)
SYSTEM PURPOSE
The emission control systems are installed to reduce the amount of CO, HC and NOx exhausted from the
engine ((3), (4) and (5)), to prevent the atmospheric release of blow±by gas±containing HC (1) and evapo-
rated fuel containing HC being released from the fuel tank (2).
The function of each system is shown in the following table.
 System Abbreviation Function
 
 
 
 
 
 
(1) Positive Crankcase Ventilation
(2) Evaporative Emission Control
(3) Exhaust Gas Recirculation
(4) Three±Way Catalytic Converter
(5) Sequential Multiport Fuel Injection* 
 
 
 
 
 
PCV
EVAP
EGR
TWC
SFI 
 
 
 
 
 
Reduces HC
Reduces evaporated HC
Reduces NOx
Reduces CO, HC and NOx
Injects a precisely timed, optimum amount of fuel for re-
duced exhaust emissions
Remark: * For inspection and repair of the SFI system, refer to the SFI section this manual.
PREPARATION
RECOMMENDED TOOLS
EQUIPMENT
 
 Tachometer 
 
 
 Torque wrench 
 
 
 Vacuum gauge 
 
± ENGINEEMISSION CONTROL SYSTEMS (2JZ±GE)EG±163