1987 MAZDA 626 fuel filter

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

FUEL SYSTEM 4B
Pressure .
regulator ^^ \ To multi-pressure tester
How to Connect Multi-Pressure Tester
Warning
Before connecting the SST, release the fuel
pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page
4B—45.)
1. Disconnect the negative battery terminal.
2. Disconnect the fuel main hose from the fuel filter.
3. Connect the SST between the fuel main hose and
fuel pump with the adapter.
Caution
Do not reverse the adapter connection.
4. Disconnect the vacuum hose from the pressure
regulator control solenoid valve. Connect the SST
vacuum hose with a three-way joint.
5. Connect the negative battery terminal.
6. Connect the SST to the battery.
86U04A-071
v *
- i\zLTest connector (Yellow)
7. Connect the terminals of the test connector (Yel-
low) with a jumper wire. Turn the ignition switch
ON to operate the fuel pump.
8. Check for fuel leaks.
Caution
After checking for fuel leakage, turn the igni-
tion switch OFF and disconnect the jumper
wire from the test connector.
86U04A-072
4B—47

4B FUEL SYSTEM
Volume Test
Warning
Before performing following procedures, re-
lease the fuel pressure to reduce the possi-
bility of injury or fire. (Refer to page 4B—45)
1. Connect a jumper wire to test connector (Yellow).
2. Disconnect the fuel return hose from fuel return
pipe.
76G04B-065
3. Turn the ignition switch ON for 10 seconds, and
check the feeding capacity with graduated
cylinder.
Feeding capacity:
220 cc (13.4 cu in)/10 sec. min.
4. If not within specification, check the fuel filter, and
fuel line.
5. Turn the ignition switch OFF and disconnect the
jumper wire.
86U04A-082
PULSATION DAMPER
1. Run the engine at idle.
2. Place a finger on the screw of the pulsation damper
head.
3. Check that pulsation is felt.
86U04A-083
4B—50

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

FUEL SYSTEM 4B
REPLACEMENT
Caution
a) Before performing the following procedure,
release the fuel pressure from the fuel sys-
tem to reduce the possibility of injury or fire
(Refer to page 4B—45).
b)When servicing the fuel system, keep
sparks, cigarettes, and open flames away
from the fuel.
76G04B-077
86U04A-101
M Fuel pump
Fuel filter
Bracket
86U04A-102
Fuel Pump
1. Remove the rear seat and disconnect the fuel
pump connector.
2. Remove the service hole cover.
3. Disconnect the fuel hoses.
4. Remove the fuel pump and fuel tank gauge as-
sembly.
5. Replace the fuel pump.
Caution
Secure the fuel pump terminals and fuel hoses
securely.
6. Install in the reverse order of removal.
4B—57

4B FUEL SYSTEM
Pressure Regulator
1. Disconnect the vacuum hose and fuel return hose.
2. Remove the pressure regulator.
3. Install in the reverse order of removal.
Tightening torque:
8—11 N-m (0.8—1.1 m-kg, 69—95 in-lb)
76G04B-084
Pulsation Damper
1. Loosen the pulsation damper and remove it.
2. Install in the reverse order of removal.
76G04B-085
^-Fuel hose
ML*? ^-Fuel pump
^silntank filter
ti* e
76G04B-086
h
tS

Is o
Sjfbj
Fuel Filter
Low pressure side
Refer to page 4B—57.
86U04A-116
High pressure side
The fuel filter must be replaced at the intervals out-
lined in the maintenance schedule.
Warning
Always work away from sparks or open
flames.
1. Disconnect the fuel hoses from the fuel filter.
2. Remove the fuel filter and the bracket.
3. Install a new filter and the bracket.
4. Connect the fuel hoses.
Note
When installing the filter, push the fuel hoses
fully onto the fuel filter and secure the hoses
with spring clamps.
4B-60

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