air filter MAZDA 626 1987 Owner's Manual

4B INTAKE AIR SYSTEM
INTAKE AIR SYSTEM
76G04B-036
This system controls the air required by the engine for operation. The system consists of the air duct,
air cleaner, air flow meter, throttle body, dynamic chamber, and intake manifold.
COMPONENT DESCRIPTIONS
Component Function Remarks
Air cleaner
Filters
air
into throttle body

Air flow meter
Detects amount
of
intake air;
sends signal
to
engine control unit Intake
air
thermo sensor and fuel pump
switch are integrated

Throttle body
Controls intake
air
quantity Integrated throttle sensor and idle switch

76G04B-037
4B—30

4B FUEL SYSTEM
FUEL SYSTEM
76G04B-057
This system supplies the fuel necessary 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 switch (incorporated in the air flow meter), and the circuit opening relay.
The fuel pump is mounted in the fuel tank to minimize the operating noise of the fuel pump. The injec-
tors are directly supplied with battery voltage through the main relay.
4B—42

FUEL SYSTEM 4B
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

Atmospheric pressure sensor
Detects atmospheric pressure; sends sig-nal
to
engine control unit

Circuit opening relay
Voltage
for
fuel pump while engine running

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 operation

Fuel filter
Filters particles from fuel

Fuel pump
Provides fuel
to
injectors • Operates while engine running
• Installed
in
fuel tank

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

Ignition switch (ST position)
Sends engine cranking signal
to
engine control unit

Inhibitor switch
Detects in-gear condition; sends signal
to
engine control unit
Switch
ON in "N" or "P"
range

Injector
Injects fuel into intake port • Controlled
by
signals from engine control unit • High-ohmic injector

Intake air thermo sensor
Detects intake
air
temperature;
sends signal
to
engine control unit Installed
in air
flow meter

Main relay
Supplies electric current
to
injectors and engine control unit

Neutral switch
Detects in-gear condition; sends signal
to
engine control unit
Switch
ON
in-gear

Oxygen sensor
Detects Oxygen concentration; sends sig-nal
to
engine control unit
Zirconia ceramic and platinum coating

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
Integrated idle switch

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-058
4B—43

4B FUEL SYSTEM
Operating time Fuel line pressure kPa
(kg/cm2, psi)
After starting: for 120
sec.
235-275
(2.4—2.8, 34—40)
After 120 sec, 186-226 (1.9-2.3, 27-33)
6. Restart the engine.
7. Check the fuel line pressure and operating times
as shown in the chart.
76G04B-127
Solenoid Valve (Pressure Regulator Control)
Inspection
1. Disconnect the vacuum hose from the solenoid
valve and vacuum pipe.
2. Blow through the solenoid valve from vacuum hose
A.
3. Check that air flows from port B.
86U04A-098
Air filter
Apply 12V
Port (J)
4. Disconnect the solenoid valve connector.
5. Connect 12V and a ground to the terminals of the
solenoid valve.
6. Blow through the solenoid valve from the vacuum
hose A.
7. Check that air flows from the valve air filter.
86U04A-099
4B-56

4B AIR INJECTION SYSTEM
AIR INJECTION SYSTEM
76G04B-095
This system supplies secondary air into the exhaust system to improve idle stability.
COMPONENT DESCRIPTIONS
Component Function Remark
Air cleaner Filters air entering throttle body
Air control valve Directs air to reed valve Installed on air cleaner
Reed valve Directs air to exhaust manifold Improves idle stability
76G04B-096
4B—68

EGR SYSTEM 4B
Apply 12V
Air filter
L
Jt Port
4. Disconnect the solenoid valve connector.
5. Connect 12V and a ground to the terminals of the
solenoid valve.
6. Blow through the solenoid valve from vacuum hose
A.
7. Check that air flows from the valve air filter.
86U04A-132
86U04A-133
86U04A-134
EGR Modulator Valve
1. Remove the EGR modulator valve.
2. Plug the No. 1 port and connect a vacuum pump
to the No. 3 port.
3. Blow into the exhaust gas port. Operate the vacu-
um pump and verify that vacuum is held.
4. Release the exhaust gas port and confirm that
vacuum is released.
EGR Control Valve
1. Manually actuate the valve by pushing on the di-
aphragm with finger.
2. Check that the spring resistance is present and the
diaphragm moves freely with no sticking or
binding.
Note
Before replacing the EGR control valve, check
the intake air and control systems.
3. Warm up the engine and run it at idle.
4. Connect a vacuum pump to the valve and apply
vacuum.
5. Check that the engine runs roughly or stalls at more
than the specified vacuum.
Specification:
40—60 mmHg (1.6—2.4 inHg)
6. If not correct, replace the EGR control valve.
86U04A-135
4B-73

4B EEC SYSTEM
Water Thermo Valve
1. Remove the water thermo valve.
2. Immerse the valve in a water-filled container.
3. Heat the water gradually and observe the tem-
perature.
4. Blow through the valve from one vacuum port and
verify that air comes out of the other port at
46—54°C (115—129°F).
86U04A-147
Three-way
check valve
86U04A-148
To canister
Pressure valve
3<> A To tank
Vacuum valve
Air filter
Three-Way Check Valve
1. Remove the check valve.
2. Blow through the valve from port A, and check that
air comes out of port B.
Next, block port B and check that air comes out
of port C.
3. Block port B.
4. Connect a vacuum pump to port A and verify that
no vacuum is held.
86U04A-149
Solenoid valve (Purge control)
Solenoid Valve (Purge control)
1. Remove the solenoid valve.
76G04B-128
4B-78

EEC SYSTEM 4B
2. Connect vacuum hoses to the valve as shown in
the figure.
3. Blow air through the valve from hose A and check
that air comes out of the valve air filter.
4. Apply 12V and ground the solenoid valve with jum-
per wires.
5. Blow air through the valve from hose A and check
that the air comes out of port B.
6. Replace, if necessary.
86U04A-151
Separator
1. Remove the separator.
2. Visually check the separator for damage.
3. Replace, if necessary.
86U04A-154
4B-79

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