Page 527 of 1865
DECELERATION CONTROL SYSTEM 4B
COMPONENT DESCRIPTIONS
Component Function Remarks
Brake light switch Detects braking operation (deceleration);
sends signal to engine control unit
Clutch switch Detects in-gear condition;
sends signal to engine control unit Switch ON when clutch pedal released
Dashpot (MTX) Prevents sudden closing of throttle valve during deceleration or shifting Adjustment speed: 1,900—2,100 rpm
Engine control unit Detects signals from input sensors and switches; cuts fuel injection
Idle switch Detects when throttle valve fully closed; sends signal to engine control unit Installed in throttle sensor
Ignition coil (-) terminal Detects engine speed; sends signal to engine control unit
Neutral switch Detects in-gear condition; sends signal to engine control unit Switch ON when in-gear
Water thermo sensor Detects coolant temperature; sends signal to engine control unit
Water thermo switch Detects radiator coolant temperature; sends signal to engine control unit ON: above 17°C (63°F)
76G04B-089
4B—65
Page 545 of 1865
CONTROL SYSTEM 4B
CONTROL SYSTEM
Atmospheric
pressue sensor
Engine control unit
Brake light switch
Clutch switch
Circuti opening
relay
E/L control unit
Air flow meter
Neutral switch
76G04B-129
The control system consists of the input devices and the engine control unit. The engine control unit
controls the fuel injection amount (EGI), fuel injection pressure, bypass air amount, switch monitor func-
tion, and fail-safe function.
4B—83
Page 546 of 1865
4B CONTROL SYSTEM
RELATIONSHIP CHART
Input Devices and Output Devices
BRAKE LIGHT SWITCH O X X X X X X X X X
ELECTRICAL LOAD CONTROL UNIT X X X X X X X X O X
P/S PRESSURE SWITCH* X X X X X X X X O X
A/C SWITCH O X X X X O O X X O
IGNITION SWITCH
(STA
POSITION) O O X O X X X X O O
INHIBITOR SWITCH o X X X O X X X X O
NEUTRAL
AND
CLUTCH SWITCH o X X X X X X X X O
OXYGEN SENSOR o X X X X X X X X X
WATER THERMO SWITCH (RADIATOR) o X X X O X X X X X
ATMOSPHERIC PRESSURE SENSOR o X X X X O X O O X
INTAKE
AIR
THERMO SENSOR o X X O X X X O O X
WATER THERMO SENSOR o X X O O O X X o X
IDLE SWITCH o o X O X X X X o X
THROTTLE SENSOR o O X X O X X X X O
AIR FLOW METER o X X X X O X X X X
IGNITION COIL o O X O O O X X o O
INPUT
DEVICES
OUTPUT
DEVICES
FUEL
INJECTION
AMOUNT FUEL
INJECTION
TIMING
PRESSURE
REGULATOR
EGR
PURGE
IDLE-UP
(A)*
IDLE-UP
(B)
IDLE-UP
(C)
rr
INPUT
DEVICES
OUTPUT
DEVICES
INJECTOR
AIR
VALVE
SOLENOID
VALVE
AIR
BYPASS
SOLENOID
VALVE
AIR
CONDITIONEI
76G04B-108
4B-84
Page 551 of 1865
CONTROL SYSTEM 4B
Terminal Input Output Connection to Voltage (After warming-up) Remarks Terminal Input Output Connection to IGN: ON Idle Remarks
1P — — — — —
1Q — — — — —
1R — — — — —
1S o Air bypass solenoid valve (Idle-up C) and P/S pressure switch
Battery voltage While solenoid ON (Refer to page 4B—35): below 1.5V
1T — — — — —
1U — — — — —
1V 0 MTX
Neutral and clutch switch
In-gear condition Clutch pedal depressed: battery voltage Clutch pedal released: below 1,5V
Neutral: constant battery voltage
1W O Test connector Test connector grounded: below 1,5V Test connector not grounded: battery voltage Green connector, 1-pin
1X — — — — —
2A o V ref 4.5—5.5V
2B 0 Air flow meter (Vc) 6-10V
2C — — Ground (E2) Approx. OV
2D o Oxygen sensor OV 0-1.OV • Cold engine: 0V at idle • After warming-up: Increase engine speed: 0.5—1.0V Deceleration: 0—0.4V
2E 0 Air flow meter (Vs) Approx. 1.7V Approx. 3—5V Increase engine speed:
voltage increases
2F — -— — —
2G 0 Throttle sensor Accelerator pedal released:
0.4—0.6 V
2H 0 Atmospheric pres-sure sensor At sea level: approx. 4.0V
21 0 Water thermo sensor 0.3—0.6 V Engine coolant temp. 20°C (68°F): approx. 2.5V
2J o Air flow meter (In-
take air thermo
sensor)
Approx. 2.3V at 20°C (68°F)
2K o Solenoid valve (Pres-
sure regulator
control)
For 120 sec. after ignition switch OFF - ON: below 1.5V
For 120 sec. after
starting: below 1.5V
Hot condition: Cool-ant temp, above 70°C (158°F) Intake air temp, above 10°C (50°F)
2K o Solenoid valve (Pres-
sure regulator
control)
Battery voltage Other conditions
2L — — — — —
2M — — —
4B-89
Page 553 of 1865
CONTROL SYSTEM 4B
Replacement
1. Disconnect the negative battery cable.
2. Remove the front console covers (right and left).
3. Disconnect the connectors from the control unit.
4. Replace the control unit.
NEUTRAL SWITCH
Inspection
1. Disconnect the neutral switch connector.
2. Connect an ohmmeter to the switch.
3. Check continuity of the switch.
Transmission Continuity
In neutral No
In other ranges Yes
4. After checking, connect the switch connector.
Note
Refer to section 7A for replacement of the
neutral switch.
CLUTCH SWITCH
Inspection
1. Disconnect the clutch switch connector.
2. Connect an ohmmeter to the switch.
3. Check continuity of the switch.
Pedal Continuity
Depressed No
Released Yes
4. After checking, connect the switch connector.
Note
Refer to section 6 for replacement of the
clutch switch.
BRAKE LIGHT SWITCH
Inspection
1. Disconnect the brake light switch connector.
2. Connect an ohmmeter to the switch.
3. Check the continuity of the switch.
Pedal Continuity
Depressed Yes
Released No
4. After checking, connect the switch connector.
Note
Refer to section 11 for replacement of the
brake switch.
4B-91
Page 562 of 1865
4C
FUEL AND EMISSION
CONTROL SYSTEMS
(FUEL INJECTION FE DOHC)
OUTLINE 4C— 2
COMPONENT APPLICATION 4C— 2
SYSTEM DIAGRAM 4C— 3
COMPONENT LOCATION 4C— 4
VACUUM HOSE ROUTING
DIAGRAM 4C— 7
SPECIFICATIONS 4C— 8
TROUBLESHOOTING GUIDE 4C— 9
TROUBLESHOOTING WITH SST.. 4C— 11
INSPECTION PROCEDURE 4C— 12
PRINCIPLE OF CODE CYCLE 4C— 13
CODE NUMBER 4C— 14
SWITCH MONITOR FUNCTION 4C— 25
INSPECTION PROCEDURE 4C— 26
IDLE ADJUSTMENT 4C— 29
IDLE SPEED 4C— 29
IDLE MIXTURE 4C— 30
INTAKE AIR SYSTEM 4C— 31
COMPONENT DESCRIPTION 4C— 31
REMOVAL 4C— 32
PARTS INSPECTION 4C— 33
REPLACEMENT 4C— 36
INSTALLATION 4C— 37
VARIABLE INERTIA CONTROL
(VIC) SYSTEM 4C— 39
COMPONENT DESCRIPTION 4C— 40
TROUBLESHOOTING 4C— 40
IDLE SPEED CONTROL
(ISC) SYSTEM 4C— 44
COMPONENT DESCRIPTION 4C— 45
TROUBLESHOOTING 4C— 46
REMOVAL 4C— 48
FUEL SYSTEM 4C— 49
COMPONENT DESCRIPTION 4C— 50
TROUBLESHOOTING 4C— 51
FUEL PRESSURE RELEASE AND
SERVICING FUEL SYSTEM 4C— 52
MULTI-PRESSURE TESTER 4C— 53
FUEL PUMP 4C— 56
PULSATION DAMPER 4C— 57
INJECTOR 4C— 57
TRANSFER PUMP CONTROL
SYSTEM 4C— 59
REPLACEMENT 4C— 60
FUEL TANK 4C— 65
PRESSURE REGULATOR
CONTROL (PRC) SYSTEM 4C— 68
COMPONENT DESCRIPTION 4C— 69
TROUBLESHOOTING 4C— 69
DECELERATION CONTROL
SYSTEM 4C— 72
COMPONENT DESCRIPTION 4C— 73
TROUBLESHOOTING 4C— 73
ELECTRONIC SPARK ADVANCE
(ESA) CONTROL SYSTEM 4C— 75
COMPONENT DESCRIPTION 4C— 76
TROUBLESHOOTING 4C— 76
EXHAUST GAS RECIRCULATION
(EGR) SYSTEM 4C- 77
COMPONENT DESCRIPTION 4C— 77
TROUBLESHOOTING 4C— 78
EVAPORATIVE EMISSION
CONTROL (EEC) SYSTEM 4C— 80
COMPONENT DESCRIPTION 4C— 80
TROUBLESHOOTING 4C— 81
POSITIVE CRANKCASE
VENTILATION (PCV) SYSTEM.... 4C— 86
COMPONENT DESCRIPTION 4C— 86
PCV VALVE 4C— 86
EXHAUST SYSTEM
(UNLEADED FUEL) 4C— 87
REMOVAL AND INSTALLATION.. 4C— 88
INSPECTION 4C— 88
EXHAUST SYSTEM
(LEADED FUEL) 4C— 89
REMOVAL AND INSTALLATION.. 4C— 90
CONTROL SYSTEM 4C— 91
RELATIONSHIP CHART 4C— 92
EGI MAIN FUSE 4C— 96
CONTROL RELAY 4C— 96
NEUTRAL SWITCH 4C— 97
CLUTCH SWITCH 4C— 97
P/S PRESSURE SWITCH 4C— 97
ENGINE CONTROL UNIT 4C— 98
E/L CONTROL UNIT 4C—102
AIR FLOW SENSOR 4C—103
THROTTLE SENSOR 4C—104
IDLE SWITCH 4C—106
WATER THERMO SWITCH 4C—106
WATER THERMO SENSOR 4C—107
OXYGEN SENSOR 4C—107
DISTRIBUTOR 4C—108
OXYGEN SENSOR HEATER 4C—109
KNOCK SENSOR 4C—109
INTAKE AIR THERMO SENSOR .. 4C—110
76G04C-001
Page 563 of 1865
4C OUTLINE
OUTLINE
COMPONENT APPLICATION
Item Unleaded fuel Leaded fuel
Air flow sensor (Hot wire type) O O
Dynamic chamber with vacuum chamber o o
INTAKE AIR SYSTEM Throttle body (Two bore) o o
Throttle sensor o X
Idle switch o o
Resonance chamber o o
VARIABLE INERTIA CONTROL SYSTEM o 0
IDLE SPEED CONTROL SYSTEM o o
Injector o o
Pressure regulator o o
Pulsation damper o o
FUEL SYSTEM Intank filter o o
Transfer pump 0 (4WS) O (4WS)
Transfer pump switch O (4WS) O (4WS)
Fuel pump control unit O (4WS) O (4WS)
PRESSURE REGULATOR CONTROL SYSTEM o o
Canister o x
EVAPORATIVE Three-way check valve o x
EMISSION CONTROL Two-way check valve X o SYSTEM Separator o o
Solenoid valves o x
EGR control valve o x
EGR SYSTEM EGR modulator valve o X
Solenoid valve o X
ELECTRONIC SPARK
ADVANCE CONTROL
SYSTEM
Igniter o o ELECTRONIC SPARK
ADVANCE CONTROL
SYSTEM Knock control function X o
Water thermo sensor o o
Water thermo switch o X
Intake air thermo sensor o o
Oxygen sensor o X
CONTROL SYSTEM Distributor o o CONTROL SYSTEM Ne signal o o
G signal o o
Clutch switch o o
Neutral switch o o
Knock sensor x o
FAIL-SAFE CONTROL SYSTEM o o
MONITOR FUNCTION o o
76G04C-002
4C—2
Page 564 of 1865
Fuel filter Solenoid valve *1 Solenoid valve *1
(No.2 purge control) (No.1 purge control)
Separator Three way
Injector
,Distributor
Fuel pump
In-take filter
Air flow sensor
Water thermo sensor
Knock sensor
switches
Intake air thermo sensor
— Water thermo switch *1 __ j—Ig. switch (ST) j_J,—lg. switch (ON) -A/C switch 'A/C magnet clutch P/S switch —Head light switch —Rear defroster switch —Cooling fun switch —Blower switch —Neutral and clutch
O) <
{/> H m
g >
o 3D >
^Throttle sensor *1
Air valve
Solenoid valve
(ISC)
EGR control valve *1
EGR modulator valve *1
0 1 CO
a *1...Unleaded fuel only
*2...Leaded fuel only
Oxygen
sensor *1
One-way check valve
Shutter valve actuator Catalytic
converter *1 Solenoid valve (VIC)
O c
m
o
