1987 MAZDA 626 water

CONTROL SYSTEM 4C
WATER THERMO SENSOR
Inspection
1. Remove the water thermo sensor.
76G04C-199
86U04A-203
2. Place the sensor in water with a thermometer and
heat the water gradually.
3. Check resistance of the sensor with an ohmmeter.
Coolant Resistance
-20°C ( —4°F) 14.5—17.8 kfl
20°C ( 68°F) 2.2-2.7 kQ
40°C (104°F) 1.0—1.3 kQ
60°C (140°F) 500—640 O
80°C (176°F) 280—350 fl
4. If not correct, replace the water thermo sensor.
OXYGEN SENSOR
Inspection of Output Voltage
1. Warm up the engine and run it at idle.
2. Disconnect the oxygen sensor connector.
3. Connect a voltmeter between the oxygen sensor
and a ground.
4. Run the engine at 4,500 rpm until the voltmeter
indicates approx. 0.7V.
76G04C-200
5. Increase and decrease the engine speed suddenly
several times. Check to see that when the speed
is increased the meter reads between 0.5V—1 .OV,
and when the speed is decreased it reads between
OV—0.4V.
6. If the voltmeter dosen't indicate as specified, re-
place the oxygen sensor.
86U04A-206
4C—107

4D
FUEL AND EMISSION
CONTROL SYSTEM
(DIESEL)
OUTLINE 4D— 2
SPECIFICATIONS 4D— 2
TROUBLESHOOTING GUIDE 4D— 3
ON-VEHICLE MAINTENANCE 4D— 4
AIR CLEANER ELEMENT 4D— 4
WATER DRAINING 4D— 4
AIR BLEEDING 4D— 4
INJECTION TIMING 4D— 5
IDLE SPEED 4D— 6
EXHAUST SMOKE 4D— 6
INTAKE AIR SYSTEM 4D— 7
STRUCTURAL VIEW 4D— 7
AIR DUCT AND AIR CLEANER 4D— 8
INTAKE MANIFOLD 4D— 9
SUPERCHARGING SYSTEM (RF-CX) 4D-10
TROUBLESHOOTING GUIDE 4D—10
ON-VEHICLE INSPECTION 4D—11
COMPREX SUPERCHARGER 4D—13
STARTING VALVE 4D—15
INTERCOOLER 4D—16
BOOST AIR TEMPERATURE SENSOR 4D—17
EXHAUST SYSTEM 4D—18
STRUCTURAL VIEW 4D—18
EXHAUST MANIFOLD 4D—19
EXHAUST PIPE AND MAIN SILENCER .... 4D—20
FUEL SYSTEM 4D—21
STRUCTURAL VIEW 4D—21
FUEL FILTER 4D—22
SEDIMENTER (GENERAL) 4D—22
WATER LEVEL SENSOR 4D—23
INJECTION PUMP 4D—24
INJECTION NOZZLE 4D—31
FUEL TANK 4D—34
76G04D-001

TROUBLESHOOTING GUIDE 4D
TROUBLESHOOTING GUIDE
Condition Condition Cause Remedy
Hard starting Fuel filter
Clogged Replace
Water or air in filter Repair
Fuel injection pump Faulty fuel cut solenoid Replace Incorrect injection timing Adjust
Air in pump Bleed
Faulty pump Replace
Fuel injection nozzle Seized needle valve Replace
Fuel dripping from nozzle Replace Incorrect valve opening pressure Adjust
Faulty glow plug Replace
Faulty cold start device Adjust or replace
Faulty supercharging system Refer to page 4D—10
Rough idle Fuel filter (Refer to "Hard starting") Fuel injection pump (Refer to "Hard starting")
Fuel injection nozzle
Seized needle valve Replace
Incorrect valve opening pressure Adjust
Improper mounting to nozzle holder Repair
Leakage of nozzle holder copper washer Replace
Fuel injection pipe Cranks Replace
Leaking from joint Repair
Improper idle speed adjustment Adjust
Engine knocking Incorrect injection timing Adjust
Low quality fuel Replace
Incorrect injection nozzle opening pressure Ajust
Seized injection nozzle needle valve Replace
Fuel dripping from injection nozzle Replace
Faulty supercharging system Refer to page 4D—10
High fuel Fuel injection pump consumption Incorrect injection timing Adjust consumption High idle speed Adjust, Inspect the dashpot
Fuel injection nozzle Incorrect valve opening pressure Repair
Fuel dripping from nozzle Replace
Leakage of nozzle holder copper washer Replace
Fuel leaking from connection Repair
Clogged fuel filter Replace
Clogged air cleaner Replace
Poor acceleration Fuel injection nozzle (Refer to "Hard starting")
Fuel injection pump (Refer to "Hard starting")
Fuel injection pipe (Refer to "Rough idle") Fuel filter (Refer to "Hard starting") Clogged air cleaner Clean or replace
Faulty supercharging system Refer to page 4D—10
Excessive exhaust Clogged air cleaner Clean or replace
smoke Improper injection timig Adjust
Faulty nozzle or nozzle holder Adjust or replace
Faulty supercharging system Refer to page 4D—10
76G04D-003
4D-3

4D ON-VEHICLE MAINTENANCE
ON-VEHICLE MAINTENANCE
76G04D-004
AIR CLEANER ELEMENT
Check the air cleaner element for excessive dirt, dam-
age, or oil. Replace if necessary.
Caution
(Wet type)
Do not clean the air cleaner element with com-
pressed air, replace if necessary.
(Dry type)
When cleaning the air cleaner element, blow
dust off from the inside first, then blow off the
outside.
(General)
1. Loosen the drain plug of the sedimenter and let
the water drain. If necessary loosen the air bleed-
ing plug.
2. Bleed air from the sedimenter.
AIR BLEEDING
From Fuel Tank to Fuel Filter
1. Loosen the air bleeding plug of the fuel filter.
2. Pump the priming pump until no air bubbles flow
from the air bleeding plug hole.
3. Depress the priming pump and tighten the air
bleeding plug.
Note
Open only the air bleeding plug of the filter.
From Fuel Filter to Injection Pump
Pump the priming pump until it becomes hard to
pump.
76G04D-007
WATER DRAINING
(ECE)
1. Loosen the drain plug of the fuel filter.
2. Pump the priming pump.
3. Bleed air from the fuel filter.
4D—4

INTAKE AIR SYSTEM 4D
INTAKE MANIFOLD
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air/exhaust leakage.
76G04D-020
3. Vacuum hose (RF-CX)
4. Water thermo switch connector
5. Intake manifold
Inspection
1. Check the intake manifold for cracks and damage.
2. Inspect the flatness of the mounting surface using
a straight edge and a feeler gauge. Replace if
necessary.
Distortion: 0.05 mm (0.002 in) max.
19—26 N m (1.9—2.6 m-kg, 14—21 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
8—11 N-m (B0—110 cm-kg, 69—95 In-lb)
8—11 Nm (80—110 cm-kg, 69—95 In-lb)
19—26 N-m (1.9—2.6 m-kg, 14—19 ft-lb)
34—49 N-m (3.5—5.0 m-kg, 25—36 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
19—26 N-m (1.9—2.6 m-kg, 14—19 ft-lb) 22—26 N-m (2.2—2.7 m-kg, 16—20 ft-lb)
22—26 N m (2.2—2.7 m-kg, 16—20 ft-lb)
8—11 N-m (80—110 cm-kg, 69—95 in-lb)
1. Comprex supercharger
(Refer to page 4D—13.: RF-CX)
2. Exhaust manifold
(Refer to page 4D—19.: RF-CX)
76G04D-021
4D-9

4D FUEL SYSTEM
76G04D-047
76G04D-048
76G04D-049
FUEL FILTER
On-Vehicle Inspection
Check for water in the fuel filter. If present drain the
water. (Refer to page 4D—4.)
Replacement
Removal
1. Disconnect the water level sensor connector (ECE).
2. Remove the water level sensor. (ECE).
3. Remove the fuel filter cartridge.
Warning
Keep fire and open flame away from the fuel
area.
Installation
1. Apply fuel to the O-ring of the fuel filter cartridge
and install it onto the filter body.
2. Install the water level sensor (ECE).
3. Connect the water level sensor connector (ECE).
4. Bleed air from fuel filter. (Refer to page 4D—4.)
5. Check for fuel leakage.
SEDIMENTER (GENERAL)
On-Vehicle Inspection
Check for water in the sedimenter. If present, drain
the water. (Refer to page 4D—4.)
4D—22

FUEL SYSTEM 4D
Replacement
1. Remove the sedimenter from the body.
2. Apply fuel to a new O-ring, and install it onto the
sedimenter body with water level sensor.
76G04D-051
WATER LEVEL SENSOR
Inspection
1. Remove the water level sensor.
(ECE)
Remove the water level sensor from the fuel filter.
(GENERAL)
Remove the water level sensor from the sedimenter
body.
76G04D-052
2. Check the water level sensor for continuity with an
ohmmeter. Replace if necessary.
ECE
Continuity : Pulled condition
No continuity: Pushed condition
76G04D-053
GENERAL
Continuity : Pushed condition
No continuity: Pulled condition
3. Apply fuel to a new O-ring and install it onto the
sensor.
4. Install the water level sensor to the fuel filter (ECE)
or the sedimenter (General).
5. Check for fuel leakage.
76G04D-054
4D-23

4D FUEL SYSTEM
Removal and Installation
1. Remove in the sequence shown in the figure, referring to the removal note for specially marked parts.
2. Install in the reverse order of removal.

59—69 N-m
(6.0—7.0 m-kg, 43-51 ft-lb)
19—26
N m
(1.9—2.6
m-kg,
14—19 ft-lb) 25—29
N-m .5—3.0 m-kg, 18—22
ft-lb)

19—26 N-m
(1.9—2.6
m-kg,
14—19 ft-lb)
76G04D-063
1. Accelerator cable
2. Injection pipe
3. Fuel hose
4. Water hose
5. Fuel cut solenoid valve con-
nector
6. Pick-up coil connector
7. Boost air hose (RF-CX)
8. Injection pump pulley lock
nut
9. Injection pump
Removal note
Injection pipe
Warning
a) Catch leaking fuel with a rag when remov-
ing the injection pipes.
b) Keep fire and open flame away from the fuel
area.
Remove the injection pipes.
76G04D-064
4D—26