1987 MAZDA 626 steering wheel

IDLE-UP SYSTEM 4B
AIR BYPASS SOLENOID VALVE
Inspection of Idle-up Signal
A/C
1. Warm up the engine and run it at idle.
2. Connect a voltmeter between terminal A and
ground.
3. Turn the A/C and blower motor switches ON.
4. Check that the meter shows battery voltage.
5. If not correct, check the A/C relay, A/C switch,
blower motor switch, fuse,and wiring harness.
76G04B-048
P/S
1. Warm up the engine and run it at idle.
2. Attach a voltmeter between the terminal F and
ground.
3. Turn the steering wheel all the way to either the
right or left.
4. Check that the meter shows OV.
5. Release the steering wheel.
6. Check that the meter shows battery voltage.
7. If not correct, check the P/S pressure switch (Re-
fer to page 4B—92) and wiring harness.
76G04B-049
High altitude compensation
1. Warm up the engine and run it at idle.
2. Connect a vacuum pump to the atmospheric pres-
sure sensor.
3. Connect a voltmeter between the terminals shown
in the following table and ground.
4. Apply vacuum to the atmospheric pressure sen-
sor as shown in the table using a vacuum pump.
5. Check that the voltmeter shows OV.
76G04B-050
J
O
6. Release the vacuum.
7. Check that the voltmeter shows battery voltage.
8. If not correct, check the atmospheric pressure sen-
sor (Refer to page 4B—99) and wiring harness.
Terminal Vacuum Amount

F Approx. 155 mmHg (6.10 inHg)
D Approx.
85
mmHg (3.35 inHg)

76G04B-051
4B-39

4B CONTROL SYSTEM
P/S pressure switch-^—^
86U04A-176
P/S PRESSURE SWITCH
Inspection
1. Disconnect the P/S pressure switch connector.
2. Connect an ohmmeter to the switch.
3. Start the engine. Check continuity of the switch
while turning the steering wheel at idle.
P/S Continuity
Turning Yes
Not turning No
4. Connect the switch connector after checking.
Note
Refer to section 10 for replacement of the P/S
pressure switch.
INHIBITOR SWITCH
Inspection
1. Disconnect the inhibitor switch connector.
2. Connect an ohmmeter to the switch.
3. Check continuity of the switch.
Position Continuity
P and N ranges Yes
Other ranges No
4. Connect the switch connector after checking.
Note
Refer to Section 7B for replacement of the in-
hibitor switch.
4B—92

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

ISC SYSTEM 4C
COMPONENT DESCRIPTION
Component Function Remark
A/C switch Detects air conditioner operation; sends
signal to engine control unit Switch ON when air conditioner
operating
Air valve When cold, supplies bypass air into dy-namic chamber • Engine speed increased to shorten warm-up period • Thermo wax type
• Installed in BAC valve
Clutch switch Detects in-gear condition; sends signal to engine control unit Switch ON when clutch pedal released
E/L control unit Detects that E/L is being applied; sends
signal to engine control unit
Engine control unit Detects signals from input sensors and switches; controls solenoid valve (Idle speed control)
Idle switch Detects when throttle valve fully closed;
sends signal to engine control unit
Installed on throttle body
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
P/S pressure switch Detects P/S operation; sends signal to engine control unit Switch ON when steering wheel turned right or left
Solenoid valve (Idle speed control) Controls bypass air amount • Controlled by duty signal from engine control unit • Installed in BAC valve
• Operates idle-up
Test connector For initial idle speed adjustment • Gerrn, 1-pin
• Idle speed feedback control cancelled when connector grounded
Water thermo sensor Detects coolant temperature; sends
signal to engine control unit
76G04C-078
4C—45

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

FUEL SYSTEM 4C
5. Connect the SST to the battery and injector.
6. Check the injection volume with a graduated con-
tainer.
Injection volume:
Approx. 66—91 cc (4.03—5.55 cu in) /15 sec.
Caution
When using the SST, make sure of the SST
number and use correct one.
7. If not correct, replace the injector.
76G04C-107
Rear seat Cushion Release Button -
76G04C-108
TRANSFER PUMP CONTROL SYSTEM (4 WHEEL
STEERING)
1. Remove the rear seat. (Refer to 14 section.)
2. Remove the fuel filler cap.
3. Turn the ignition switch ON.
Note
a) The tank should be more than 1/3 full.
b) Due to the delay timer, transfer pump oper-
ation begins approx. 10 sec. after the igni-
tion switch is turned ON.
4. Listen for the operational sound of the transfer
pump.
5. Install the fuel filler cap.
6. If no sound was heard, check the voltage at the
transfer pump connector.
Terminal (wire) Voltage
A, C (WG) Approx. 12V
I, J (B) OV
86U04B-075
I C A
lb d
cp a • • •
J
76G04C-211
7. If the voltages are correct, replace the transfer
pump.
8. If not correct, disconnect the transfer pump con-
nector.
9. Check the voltage at the terminals below.
Terminal (wire) Voltage
A, C (WG) Approx. 12V
I, J (B) OV
10. If the voltages are correct, replace the transfer
pump.
4C—59

FUEL SYSTEM 4C
FUEL TANK
Removal
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 4C—52.)
b)When removing the fuel tank, keep sparks, cigarettes, and open flames away from the
fuel tank.
Remove in the sequence shown in the figure.
76G04C-125
Note
Drain the fuel from the fuel tank before removing the tank.
1. Remove fuel filler cap.
2. Fuel pump connectors
3. Fuel hoses
4. Steering angle transfer shaft (4-wheel
steering)
(Refer to section 10)
5. Cross member (4-wheel steering)
6. Evaporative hoses
7. Fuel filler hose
8. Breather hose
9. Parking cable bracket
10. Fuel tank strap
11. Fuel tank
4C-65

FUEL SYSTEM 4C
Installation note
Hoses
1. Push the ends of the main fuel hose, fuel return
hose, and evaporation hoses onto the fuel tank fit-
tings at least 25 mm (1.0 in).
2. Push the fuel filler hose onto the fuel tank pipe and
filler pipe at least 35 mm (1.4 in).
Steering angle transfer shaft
(4-wheel steering)
Refer to section 10
4C—67