fuel MAZDA 626 1987 Owners Manual

4A EGR SYSTEM
EXHAUST GAS RECIRCULATION
(EGR)
SYSTEM
FE 8VALVE—UNLEADED FUEL
This system introduces exhaust gas into the intake manifold to reduce NOx emissions.
4A—64

IDLE-UP CONTROL SYSTEM 4 A
FE (Middle East) and F6 (General)
Possible cause
jrvo

diaphragm

3
jrvo

diaphragm

n c o> (0
E 3 3 O
® >
a >
•o o c e
£ O **
S M O
£ O
'i (0 (0
O <
o a
o E W 0)
lm Q.
c a k 4) -
9-5
"S "5 (O > CO < a. DC H Js * OC M
Page 4A—72 4A—74 4A—74 Section 15 4A—75 Section 16
Checking order 1 2 3 4 5 6 7 8
76G04A-136
FE 8Valve—Unleaded Fuel
Posible cause

Engine

control

unit

terminal

Servo

diaphragm

Vacuum

signal

Solenoid

valve £ O **
S CO O
£ U
S <0 U) Relay
(for
A/C) ** n ** w o E «
Refrigerant
pressure

switch
H D I Servo

diaphragm

Vacuum

signal

Solenoid

valve
< a. Relay
(for
A/C)
H Refrigerant
pressure

switch

Page 4A—91 4A—72 4A—74 4A—74 Section 15 4A—75 Section 16
Checking order 9 1 2 3 4 5 6 7 8
76G04A-137
4A—71

4A IDLE-UP CONTROL SYSTEM
76G04A-144
76G04A-145
76G04A-146
Vacuum Signal [Equipped with A/C, only FE and
F8 (Except Middle East and General)]
1. Start the engine and run it at idle.
2. Disconnect the vacuum hose from the servo di-
aphragm.
3. Place a finger over the hose.
4. Increase the engine speed, and check for vacuum.
Engine model Engine speed Vacuum
pj| (Except Middle) Below 2,300 rpm Yes pj| (Except Middle) Above 2,300 rpm No
FE (Unleaded fuel) Below 1,500 rpm Yes FE (Unleaded fuel) Above 1,500 rpm No
F6 (Singapore) Below 2,100 rpm Yes F6 (Singapore) Above 2,100 rpm No
General and Middle East
1. Start the engine and run it at idle.
2. Disconnect the vacuum hose from the servo di-
aphragm.
3. Place a finger over the hose.
4. Operate the A/C or P/S.
5. Check that vacuum is felt.
P/S Switch
1. Start the engine and run it at idle.
2. Disconnect the power steering switch connector.
3. Connect an ohmmeter to the power steering
switch.
4. Turn the steering wheel all the way to either the
right or left, and check for continuity.
P/S Continuity
Operated Yes
Not operated No
5. Replace if necessary.
Solenoid Valve (A/C)
1. Disconnect vacuum hose A from the servo di-
aphragm.
2. Disconnect vacuum hose B from the solenoid
valve.
3. Disconnect the solenoid valve connector.
4. Blow air through the valve from hose A and check
that it comes out of port C.
76G04A-147
4A-74

4 A EVAPOTATIVE EMISSION CONTROL SYSTEM
EVAPORATIVE EMISSION CONTROL SYSTEM
(MIDDLE EAST)
76G04A-155
Operation
Cold engine — below 50°C (122°F)
The No. 1 purge control valve does not operate because the vacuum passage of the water thermo
valve is opened to the atmospheric air side.
Warm engine — above 50 °C (122°F)
1. During normal driving, the carburetor vacuum signal is led to the No. 1 purge control valve with
the result that fuel vapors are drawn into the intake manifold.
4A—78

4A CONTROL SYSTEM
RELATIONSHIP CHART
O: Related
X
: Not
related
IGNITION COIL
X X
O O O
X
O
X

WATER
THERMO
SWITCH
RADIATOR O O
X X X X
o O WATER
THERMO
SWITCH INTAKE
MANIFOLD o
X X X X
O o
X

VACUUM SWITCH
X X X X X X X
O
IDLE SWITCH
X X
O O O
X X X

A/C SWITCH
X X X X X
O
X X

P/S SWITCH
X X X X X X X X

E/L SWITCHES
/ Headlight Switch


( Rear defroster switch
J

\ Fan speed control switch
/
X X X X X
O
X X

INHIBITOR SWITCH
X X X X X
O O
X

ENGINE CONTROL UNIT
X
o O O O O o O

\
INPUT

DEVICE

AND
ENGINE

CONTROL

UNIT

OUTPUT
DEVICE
PTC
HEATER

CHOKE

OPENER
(FE
and
F8
—
ECE,
Hong
Kong,
&

Singapore)

COASTING
LEANER
COAST

ENRICHMENT

SOLENOID

VALVE
AIR

BYPASS
SOLENOID
VALVE
IDLE-UP
SOLENOID
VALVE
IGNITION
TIMING
CONTROL
SYSTEM
MAIN
AIR
BLEED
CONTROL
SYSTEM

*
FE
8Valve—Unleaded Fuel:
O
(Related)
General and
FE
12Valve—ECE, Hong Kong, Singapore:
X
(Not related)

76G04A-167
4A—84

CONTROL SYSTEM 4 A
Terminal (Wire color) Connected to Condition Voltage

0 (BY)
Ignition switch*
(START position) Ignition switch
ON
Below 1.5V 0 (BY)
Ignition switch*
(START position) Cranking Battery voltage
P
(LW) Solenoid valve (A/C) A/C switch
ON
and engine speed below approx.
2,300
rpm
Below 1,5V
Others Battery voltage
Q (YW) Idle-up solenoid valve Headlight switch ON, rear defroster switch ON,
fan
speed control switch
is
3rd
or
4th position, A/C oper-ated,
or
engine coolant temperature below 72°C (162°F)
Below 1,5V
Others Battery voltage
R
(LB)
Fan speed control switch Fan speed control switch
in
3rd
or
4th position Below 1,5V R
(LB) Fan speed control switch OFF Battery voltage
*
Not
used
76G04A-173

{
Q
0
><
K
X
G E C A
^

R P
R X
J H F D B

FE 8Valve — Unleaded Fuel
Terminal (Wire color) Connected to Condition Voltage

A
(L)
Coast enrichment solenoid valve Engine speed approx. 1,500—2,300 rpm and idle switch
ON

Below 1,5V A
(L)
Coast enrichment solenoid valve
Others Battery voltage
B
(B)
Ground
—
Below 1,5V
C (LB)
Air bypass solenoid valve Engine speed above approx. 3,500 rpm and idle
switch
ON

Below 1,5V C (LB)
Air bypass solenoid valve
Others Battery voltage
D
(YL)
Ignition coil Ignition switch
ON or
engine running Battery voltage
E
— — —

F
(BW)
Ignition switch Ignition switch
ON
Battery voltage
G (YW) Slow fuel cut solenoid valve Engine speed above approx. 2,300 rpm and idle
switch
ON

Battery voltage G (YW) Slow fuel cut solenoid valve
Others Below 1.5V
H
(LW) A/C switch A/C operated and engine speed above approx.
1,500 rpm
Battery voltage H
(LW) A/C switch
A/C not operated
or
engine speed below approx.
1,500 rpm
Below 1,5V

4A—91

4A CONTROL SYSTEM
Idle switch
Adjust screw
76G04A-180
76G04A-181
5. Increase the engine speed to more than 2,000 rpm
and decelerate gradually.
6. Check the voltage.

Specification
Engine speed
^^^

FE 8Valve—
Unleaded Fuel
& F6 Sin-
gapore
Others
At idle below 1,5V Battery voltage
Above 1,000—1,100 rpm Battery voltage below 1.5V

7. If the voltage is not within specification, turn the ad-
just screw to adjust.
VACUUM SWITCH
On-Vehicle Inspection
1. Run the engine at idle.
2. Connect a voltmeter to the vacuum switch connec-
tor terminal wire (LB).
Voltage: Approx. 12V
3. Disconnect the vacuum hose from the vacuum
switch, and plug it.
4. Check the voltage.
Voltage: Less than 1.5V
Off-Vehicle Inspection
Inspection
1. Remove the vacuum switch.
2. Connect a vacuum pump to the vacuum switch.
3. Connect an ohmmeterto the vacuum switch, and
check the continuity between the switch terminals.

Vacuum Continuity
MTX: More than 300 mmHg (11.8 inHg) No ATX: More than 200 mmHg (7.9 inHg) No
Others Yes

76G04A-182
4A—94

4A EXHAUST SYSTEM
EXHAUST SYSTEM
EXCEPT FE 8VALVE—UNLEADED FUEL
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
Torque specifications
1. Center silencer and main silencer
2. Brackets
76G04A-187
3. Front silencers
4. Exhaust manifolds
Inspection
Visually check the exhaust system for cracks or
damage.
4A—96

EXHAUST SYSTEM 4A
FE 8 VALVE-UNLEADED FUEL
Removal and Inspection
1. Remove in the sequence shown in the figure
2. Install in the reverse order of removal.
Torque Specifications

L

22—28 N-m (2.2—2.9 m-kg, 16—21 ft-lb)
34—49 N-m (3.5—5.0 m-kg, 26—36 ft-lb)
55—60 N-m (5.6—8.2 m-kg, 40—59 ft-lb)
.8—11 Nm .8—1.1 m-kg, 69—95 in-lb)
N-m 3 m-kg, 25—38 ft-lb)
76G04A-189
1. Main silencer
2. Middle pipe
3. Pre-silencer
4. Catalytic converter
5. Bracket
6. Front pipe
Inspection
1. Check the catalytic converter and exhaust pipe for
deterioration or restriction.
2. Check the insulation covers welded onto the cata-
lytic converter for damage.
Note
If the insulation cover is touching the catalytic
converter housing, excessive heat at the floor
will occur.
76G04A-190
4A-97

FUEL AND EMISSION
CONTROL SYSTEMS
(FUEL INJECTION FE)
OUTLINE 4B— 2
SYSTEM DIAGRAM 4B— 2
COMPONENT LOCATION 4B— 3
VACUUM HOSE ROUTING
DIAGRAM 4B— 5
SPECIFICATIONS 4B— 6
TROUBLESHOOTING GUIDE 4B— 7
TROUBLESHOOTING
PROCEDURE 4B— 7
TROUBLESHOOTING WITH SST.... 4B— 9
INSPECTION PROCEDURE 4B—10
AFTER-REPAIR PROCEDURE 4B—10
PRINCIPLE OF CODE CYCLE 4B—12
CODE NUMBER 4B—13
SWITCH MONITOR FUNCTION 4B—25
INSPECTION PROCEDURE 4B—26
IDLE SPEED 4B—29
IDLE MIXTURE 4B—29
INTAKE AIR SYSTEM 4B—30
COMPONENT DESCRIPTIONS 4B—30
REMOVAL 4B—31
PARTS INSPECTION 4B—32
INSTALLATION 4B—34
IDLE-UP SYSTEM 4B—35
COMPONENT DESCRIPTIONS 4B—36
TROUBLESHOOTING 4B—37
AIR VALVE 4B—38
AIR BYPASS SOLENOID VALVE ... 4B—39
FUEL SYSTEM 4B—42
COMPONENT DESCRIPTIONS 4B—43
TROUBLESHOOTING 4B—44
FUEL PRESSURE RELEASE AND
SERVICING FUEL SYSTEM 4B—45
MULTI-PRESSURE TESTER 4B—46
FUEL PRESSURE 4B—48
FUEL PUMP 4B—49
PULSATION DAMPER 4B—50
INJECTOR 4B—51
PRESSURE REGULATOR
CONTROL SYSTEM 4B—53
COMPONENT DESCRIPTIONS 4B—54
TROUBLESHOOTING 4B—55
REPLACEMENT 4B—57
FUEL TANK 4B—61
DECELERATION CONTROL
SYSTEM 4B—64
COMPONENT DESCRIPTIONS 4B—65
TROUBLESHOOTING 4B—66
AIR INJECTION SYSTEM 4B—68
COMPONENT DESCRIPTIONS 4B—68
TROUBLESHOOTING 4B—69
EXHAUST GAS RECIRCULATION
(EGR) SYSTEM 4B—71
COMPONENT DESCRIPTIONS 4B—71
TROUBLESHOOTING 4B—72
EVAPORATIVE EMISSION
CONTROL (EEC) SYSTEM 4B—74
COMPONENT DESCRIPTIONS 4B—74
TROUBLESHOOTING 4B—75
POSITIVE CRANKCASE
VENTILATION (PCV) SYSTEM 4B—80
COMPONENT DESCRIPTION 4B—80
EXHAUST SYSTEM 4B—81
REMOVAL AND INSTALLATION ... 4B—82
INSPECTION 4B—82
CONTROL SYSTEM 4B—83
RELATIONSHIP CHART 4B—84
EGI MAIN FUSE 4B—86
MAIN RELAY 4B—86
CIRCUIT OPENING RELAY 4B—86
ENGINE CONTROL UNIT 4B—87
NEUTRAL SWITCH 4B—91
CLUTCH SWITCH 4B—91
BRAKE LIGHT SWITCH 4B—91
P/S PRESSURE SWITCH 4B—92
INHIBITOR SWITCH 4B—92
E/L CONTROL UNIT 4B—93
AIR FLOW METER 4B—94
THROTTLE SENSOR 4B—95
WATER THERMO SENSOR 4B—97
WATER THERMO SWITCH 4B—97
OXYGEN SENSOR 4B—98
ATMOSPHERIC PRESSUFfE
SENSOR 4B—99
76G04B-001