fuel cap MAZDA 626 1987 User Guide

IDLE SPEED AND IDLE MIXTURE 4A
76G04A-063
76G04A-064
4. Turn the mixture adjust screw to adjust the CO con-
centration.
5. Recheck the idle speed.
6. Fit a new blind cap onto the mixture adjust screw.
Idle Mixture [FE 8Valve—Unleaded Fuel]
Adjustment of the idle mixture is normally un-
necessary.
But if it is necessary, adjust it as follows.
Note
Do not insert the exhaust gas analyzer into the
tail pipe.
Before adjust the idle mixture, check and set
the idle speed.
1. Disconnect the secondary air hoses.
2. Insert an exhaust gas analyzer into the hose and
plug it to prevent leakage.
3. Start the engine and run it at idle.
4. Measure the CO concentration.
5. Remove the blink cap from the mixture adjust
screw.
6. Turn the mixture adjust screw and adjust the CO
level.
CO concentration: 2.0 ± 0.5%
7. If the idle speed fails to meet specification as the
result of the above steps, adjust the idle.
8. Reconnect the secondary air hoses.
9. Fit a new blind cap onto the mixture adjust screw.
76G04A-065
4A-39

4B OUTLINE
SPECIFICATIONS
Item Specification

Idle speed rpm MTX: 800 +5„° (Neutral), ATX: 900 +5S
(P
range)

Throttle body

Type Horizontal draft (1 -barrel)
Throat diameter mm (in) 50 (2.0)

Air flow meter

E2-VS More than
20

E2-VC 100-300
Resistor
Q
E2-VB 200—400 Resistor
Q

E2-THA -20°C
(
—4°F) 13,600-18,400 20°C
(
68°F) 2,210-2,690 60°C (140°F)
493- 667
Air cleaner

Element type Oil permeated

Fuel pump

Type Impeller
(in
tank)
Output pressure kPa (kg/cm2,
psi)
441-588 (4.5-6.0, 64—85)
Feeding capacity cc (cu in)/10 sec. 220 (13.4) minmum

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
TvDe
Hiqh-ohmic
Type
of
drive Voltage
Resistance
fi
12-16
Injection amount cc (cu
in) 15
seconds 38—53 (2.3-3.2)

Fuel tank

Capacity liters (US gal, Imp gal) 60 (15.9, 13.2)

Fuel

Soecification Unleaded reaular

76G04B-506
4B—6

IDLE ADJUSTMENT 4B
76G04B-034
76G04B-035
Idle mixture
Automatic
Control
Function
Engine Control Unit

IDLE
ADJUSTMENT
IDLE SPEED
Preparation
1) Check the condition of the engine (plugs, leaks in
hoses, etc.).
2) Make sure all accessories are OFF.
3) Warm up the engine and run it for three minutes
at 2,500—3,000 rpm in neutral.
4) Check the initial ignition timing and adjust if
necessary.
Inspection and Adjustment
Caution
Disconnect the air bypass solenoid connec-
tor when checking and adjusting the idle
speed.
1. Check that the idle speed is within specification.
Specification:
MTX—800 +58 rpm
ATX—900 +58 rpm (P range)
2. If the idle speed is not within specification, remove
the blind cap from the throttle body and adjust it
by turning the air adjust screw.
IDLE MIXTURE
Because an automatic compensation function
for air/fuel mixture is built into the engine con-
trol unit, it is not necessary to check and adjust
the idle mixture.
86U04A-049
4B-29

4B FUEL SYSTEM
76G04B-061
I i. i { 1 t' i 1 I • i i 1 1 "1 —r
1 . . • , 1 ,
EDO 250
86U04A-074
w Test connector
(Yellow)
86U04A-075
Lever
To fuel pump To pulsation damper
FUEL PRESSURE
Note
a) When inspecting fuel pressure, use the
SST. (Refer to page 4B—47).
b)Warm up the engine to normal operating
temperature.
Injection Pressure
1. Set the lever on the adapter as shown in the figure.
2. Run the engine and measure the injection pres-
sure at various speeds.
Injection pressure: Approx. 235—275 kPa
(2.4—2.8 kg/cm2, 34—40 psi)
3. If not within specification, check the fuel pump pres-
sure and fuel line pressure.
Fuel Pump Pressure
1. Connect the terminals of the test connector (Yel-
low) with a jumper wire.
2. Turn the ignition switch ON to operate the fuel
pump.
3. Set the lever on the adapter as shown in the figure.
4. Check the fuel pump pressure.
Fuel pump pressure: 441—588 kPa
(4.5—6.0 kg/cm2, 64—85 psi)
5. If the fuel pump pressure is not within specifica-
tion, check the following;
No pressure
• Fuel pump operation (Refer to page
4B—49.)
Low pressure
• Fuel pump feeding capacity (Refer to
page 4B—50.)
High pressure
• Replace the fuel pump
6. After checking the fuel pump pressure, disconnect
the jumper wire from the test connector.
76G04B-062
4B—48

FUEL SYSTEM 4B
76G04B-126
86U04A-078
V^AN.
- Test connector
(Yellow)
76G04B-063
Fuel Line Pressure
1. Start the engine and run it at idle.
2. Set the lever on the adapter as shown in the figure.
3. Check the fuel line pressure.
Fuel line pressure: Approx. 186—226 kPa
(1.9—2.3 kg/cm2, 27—33 psi)
4. If not within specification, check the vacuum hose.
5. Disconnect the vacuum hose from pressure regu-
lator, and place a finger over the end of the hose.
6. Check the fuel line pressure.
Fuel line pressure: 235—275 kPa
(2.4—2.8 kg/cm2, 34—40 psi)
7. If not within specification, replace the pressure
regulator.
8. Connect the vacuum hose to pressure regulator.
FUEL PUMP
Operation Test
1. Connect a jumper wire to the test connector
(Yellow).
2. Remove the fuel filler cap.
3. Turn the ignition switch ON.
4. Listen for operational sound of the fuel pump at
the filler inlet.
5. Install the fuel filler cap.
6. If no sound is heard, check the voltage at the fuel
pump connector (WY wire and a ground).
Voltage: 12V
7. If the voltage is normal, replace the fuel pump.
8. If not correct, check the circuit opening relay (Re-
fer to page 4B—86) and its circuits.
9. Disconnect the jumper wire.
76G04B-064
4B—49

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

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

4C IDLE ADJUSTMENT
76G04C-048
Idle speed
Automatic
Control
Function
Engine Control Unit
76G04C-049
76G04C-050
3. Remove the blind cap and adjust the initial idle
speed to specification by turning the air adjust
screw.
Initial idle speed: 750 ± 50 rpm
4. After adjusting the idle speed, install the blind cap
and disconnect the jumper wire from the test con-
nector.
5. Recheck the idle speed.
6. If not within specification, check the idle speed con-
trol (ISC) system.
IDLE MIXTURE (Unleaded Fuel)
An automatic compensation function for air/fuel
mixture is built into the engine control unit, it
is not necessary to check and adjust the idle
mixture.
IDLE MIXTURE (Leaded Fuel)
Note
Before checking or adjusting the idle mixture,
check and adjust the idle speed, if necessary.
1. Insert a gas analyzer pick-up into the tail pipe.
2. Check that the CO and HC concentrations are with-
in specification.
CO concentration: 1.5 ± 0.5%
HC concentration: Less than 1,000 PPM
3. If the CO or HC concentration is not within specifi-
cation, turn the adjust screw
with
the SST to adjust.
76G04C-051
4C-30

FUEL SYSTEM 4C
i i 1 1 1 i i
r.:.:::r t t t t t izn —i—i—i—i—i—i—i—i—
2DD 350
86U04A-074
2. Run the engine and measure the injection pres-
sure at various speeds.
Injection pressure: Approx. 235—275 kPa
(2.4—2.8 kg/cm2, 34—40 psi)
3. If not within specification, check the fuel pump pres-
sure and fuel line pressure.
Fuel Pump Pressure
1. Connect the terminals of the test connector (Yel-
low) with a jumper wire.
2. Turn the ignition switch ON to operate the fuel
pump.
3. Set the lever on the adapter as shown in the figure.
4. Check the fuel pump pressure.
Fuel pump pressure: 441—588 kPa
(4.5—6.0 kg/cm2, 64—85 psi)
5. If the fuel pump pressure is not within specifica-
tion, check the following;
No pressure
• Fuel pump operation (Refer to page
4C—56.)
Low pressure
• Fuel pump feeding capacity (Refer to
page 4C—56.)
High pressure
• Replace the fuel pump
6. After checking the fuel pump pressure, disconnect
the jumper wire from the test connector.
Fuel Line Pressure
1. Start the engine and run it idle.
2. Set the lever on the adapter as shown in the figure.
3. Check the fuel line pressure.
Fuel line pressure: Approx. 186—226 kPa
(1.9—2.3 kg/cm2, 27—33 psi)
4. If not within specification, check the pressure regu-
lator vacuum hose.
4C-55

4C FUEL SYSTEM
86U04A-078
76G04C-097
76G04C-098
„\W cLTest connector (Yellow)
'-/jumper wire \\ \ •
5. Disconnect the vacuum hose from pressure regu-
lator, and place a finger over the end of the hose.
6. Check the fuel line pressure.
Fuel line pressure: 235—275 kPa
(2.4—2.8 kg/cm2, 34—40 psi)
7. If not within specification, replace the pressure
regulator.
8. Connect the vacuum hose to pressure regulator.
FUEL PUMP
Operation Test
1. Connect a jumper wire to the test connector
(Yellow).
2. Remove the fuel filler cap.
3. Disconnect transfer pump connector (8-pin).
4. Turn the ignition switch ON.
5. Listen for operational sound of the fuel pump at
the filler inlet.
6. Install the fuel filler cap.
7. If no sound was heard, check the voltage at the
fuel pump connector (WY wire and a ground).
Voltage: 12V
8. If the voltage is normal, replace the fuel pump.
9. If not correct, check the control relay and circuit
(Refer to page 4C—96.)
10. Disconnect the jumper wire.
Volume Test
Warning
Before performing the following procedures,
release the fuel pressure from the fuel system
to reduce the possibility of injury or fire.
(Refer to page 4C—52)
1. Connect a jumper wire to test connector (Yellow).
2. Disconnect the fuel return hose from fuel return
pipe.
76G04C-099
4C-56