fuel pump MAZDA 626 1987 Repair Manual

4B EEC SYSTEM
EVAPORATIVE EMISSION CONTROL
(EEC)
SYSTEM
Engine control unit
Solenoid valve
(Purge control)
Vacuum
switch
valve x
From water thermo valve To dynamic -chamber
Three-way
check valve
Orifice Charcoal
canister
From fuel tank
No.2 purge
control valve
Fuel tank
86U04A-136
This system stores fuel vapor generated in the fuel tank in the canister when the engine is not running.
The fuel vapor is stored in the canister until it is drawn into the dynamic chamber and burned when
the engine is started.
COMPONENT DESCRIPTIONS
Component Function Remarks
Air flow meter Detects amount of intake air; sends signal to engine control unit
Intake air thermo sensor and fuel pump
switch are integrated
Charcoal canister Stores fuel tank fumes when engine
stopped
Engine control unit Detects signals from input sensors and switches; controls solenoid valve (Purge control)
Ignition coil (-)
terminal Detects engine speed; sends signal to
engine control unit
Separator Prevents fuel from flowing into charcoal canister
Solenoid valve (Purge control) Controls vacuum line to vacuum switch valve
Three-way check valve Controls pressure in fuel tank
Vacuum switch valve Regulates evaporative fumes from canis-
ter to intake manifold
Water thermo sensor Detects coolant temperature; sends signal to engine control unit
Water thermo valve Controls vacuum applied to No.1 purge control valve and solenoid valve (Purge control)
Opens vacuum line above 54°C (129°F)
76G04B-104
4B—74

4B CONTROL SYSTEM
AIR FLOW METER
Potentiometer
Intake air thermo
sensor Fc EI E2 VB VC VS THA
Fuel pump switch
Connector-—
I
lOQDOQOD i
69G04C-100
Inspection
1. Remove the air flow meter. (Refer to page 4B—31)
2. Check the air flow meter body for cracks.
3. Verify that the measuring plate moves smoothly.
4. Disconnect the connector from the air flow meter.
5. Using an ohmmeter, check resistance between the
terminals with the measuring plate fully closed and
fully open.
6. Connect the connector to the air flow meter after
inspecting.
76G04B-112
Terminal Resistance (Q) Terminal Fully closed | Fully open
E2<->VS More than 20
E2«VC 100-300
E2«VB 200-400
E2«THA (Intake air thermo sensor)
-20°C (—4°F) 13.6-18.4 kfi 20°C (68°F) 2.21-2.69 kfi 60°C (140°F) 493—667 0
Ei<->Fc OO 0
Note
Refer to page 4B—31 for replacement of the
air flow meter.
76G04B-113
4B—94

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

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

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

4C OUTLINE
SPECIFICATIONS
Item Engine type Unleaded Fuel Leaded Fuel
Idle speed rpm 750 ± 50
Throttle body
Type Horizontal draft (2-barrel)
Throat diameter mm (in) No. 1 46 (1.8) Throat diameter mm (in) No. 2 40 (1.6)
Fuel pump
Type Impeller (in tank)
Output pressure kPa (kg/cm2, psi) Main pump: 441-588 (4.5—6.0, 64—85) Transfer pump: 20—25 (0.20—0.25, 2.8—3.6)
Feeding capacity cc (cu in)/10 sec. Main pump: More than 220 (13.4) Transfer pump: More than 190 (11.6)
Fuel filter
Type Low pressure side Nylon element Type High pressure side Paper element
Pressure regulator
Type Diaphragm
Regulating pressure kPa (kg/cm2, psi) 235-275 (2.4 -2.8, 34-40)
Injector
Type High-ohmic
Type of drive Voltage
Resistance G 12--16
Injection amount cc (cu in)/15 sec. 66-91 (4.03-5.55)
Idle speed control valve
Solenoid resistance a 6.3--9.9
Fuel tank
Capacity liters (US gal, Imp gal) 60 (15.9, 13.2), 57 (15.0, 12.5): 4-wheel steering vehicle
Air cleaner
Element type Dry
Fuel
Specification Unleaded (95 RON or more) Leaded or unleaded fuel
(95 RON or more)
76G04C-008
4C-8

VIC SYSTEM 4C
System Inspection
1. Warm up the engine to normal operating temper-
ature and run it at idle.
2. Check that the rod has been pulled into the ac-
tuator.
76G04C-068
3. Increase the engine speed and check that the rod
is released above specification.
Specification:
Approx. 5,200 rpm....Unleaded fuel
Approx. 5,400 rpm....Leaded fuel
76G04C-069
Shutter Valve Actuator
1. Disconnect the vacuum hose from the actuator,
and connect a vacuum pump to the actuator.
2. Apply approx. 200 mmHg (7.9 inHg) vacuum
and check that the rod is pulled into the actuator.
76G04C-070
VIC Solenoid Valve
1. Disconnect the vacuum hoses from the solenoid
valve.
2. Blow through the valve from port A and check that
air flows from port B.
76G04C-071
4C—41

4C VIC SYSTEM
3. Disconnect the solenoid valve connector and con-
nect 12V and a ground to the terminals of the sole-
noid valve.
4. Blow through the valve from port A and check that
air flows from the air filter.
76G04C-072
Electrical Signal
1. Connect a voltmeter to the VIC solenoid valve (O
wire).
2. Increase the engine speed and note the voltmeter
reading.
Voltmeter reading Unleaded fuel Leaded fuel
Approx. 12V Below 5,200 rpm Below 5,400 rpm
Below 2.0V Approx. 5,100 rpm Approx. 5,300 rpm
76G04C-073
Vacuum Signal
1. Disconnect the vacuum hose from the actuator.
2. Place a finger over the port opening and check
that air is pulled in at idle.
3. Increase the engine speed above specification and
check that air is not pulled in.
Specification:
Approx. 5,200 rpm Unleaded fuel
Approx. 5,400 rpm Leaded fuel
4. Connect the vacuum hose.
76G04C-074
76G04C-075
4C-42
Vacuum Chamber
1. Disconnect vacuum hose A from the dynamic
chamber.
2. Connect the vacuum pump to the dynamic
chamber.
3. Apply vacuum and check that it is held.
4. If not correct, check the one-way check valve for
vacuum leakage. (Refer to page 4C—43.)
Note
10 mm Hg (0.39 inHg) drop per 30 seconds is
allowable.
5. If the one-way check valve is good, check the dy-
namic chamber.

FUEL SYSTEM 4C
FUEL SYSTEM
76G04C-087
This system supplies the necessary fuel for combustion at a constant pressure to the injectors. Fuel
is metered and injected into the intake manifold according to the injection control signals from the en-
gine control unit. It consists of the fuel pump, fuel filters, delivery pipe, pulsation damper, pressure
regulator, injectors, fuel pump control unit, and the control relay.
The fuel pump is mounted in the fuel tank to minimize the operating noise of the fuel pump. The injec-
tors directly supplied with battery voltage through the control relay. The connector of the injectors is
white to distinguish the injectors for FE DOHC from those of other engines.
Due to the installation of the steering angle transfer shaft for the 4-wheel steering (4WS) the fuel tank
of 4WS vehicles is designed with separate right and left sections. A transfer pump is used to pump
fuel from the left side to the right side.
4C—49

4C FUEL SYSTEM
COMPONENT DESCRIPTION
Component Function Remark
Air flow sensor Detects amount of intake air;
sends signal to engine control unit
Clutch switch Detects in-gear condition; sends signal to engine control unit Switch ON when clutch pedal released
Engine control unit Detects signals from input sensors and switches; controls injector and fuel pump operations
Fuel filter Filters fuel
Fuel pump Provides fuel to injectors • Operates while engine running
• Installed in fuel tank
Fuel pump control unit (4WS) Monitors fuel level in left section; controls transfer pump operation
G signal pick-up Detects No.1 cylinder TDC; sends signal to engine control unit Installed in distributor
Idle switch Detects when throttle valve fully closed; sends signal to engine control unit Installed on throttle body
Ignition switch (ST position) Sends engine cranking signal to engine control unit
Injector Injects fuel into intake port • Controlled by signals from engine control unit • High-ohmic injector
Intake air thermo sensor Detects intake air temperature; send signal to engine control unit
Control relay Supplies electric current to injectors fuel pump and engine control unit
Ne signal pick-up Detects crank angle at 180° intervals; sends signal to engine control unit Installed in distributor
Neutral switch Detects in-gear condition; sends signal to engine control unit
Switch ON when in gear
Oxygen sensor (Unleaded fuel) Detects oxygen concentration; sends signal to engine control unit
• Zirconia ceramic and platinum coating • Integrated heater coil
Pressure regulator Adjusts fuel pressure supplied to injectors
Pulsation damper Absorbs fuel pulsation
Throttle sensor Detects throttle valve opening angle;
sends signal to engine control unit
Installed on throttle body
Transfer pump (4WS) Pumps fuel from the left to the right side Controlled by fuel pump control unit
Transfer pump switch (4WS) Detects fuel level in left section;
sends signal to control unit
Water thermo sensor Detects coolant temperature; sends signal to engine control unit
Water thermo switch (Unleaded fuel) Detects radiator coolant temperature; sends signal to engine control unit ON: above 17°C (63°F)
76G04C-088
4C-50