1992 MAZDA PROTEGE fuel pressure

FUEL SYSTEM
Fuel pump maximum pressure
DISCONNECT CONNECTOR
TO RELEASE FUCL PRESSURE
Warning
23UOFX-11
OBUOFX-144 l
Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-121 .) 4
1
2
23UOFX-15 7
1. Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge to the fuel main pipe and
plug the outlet of the fuel pressure gauge as shown. (Install
clamps as shown.)
3. Connect the negative battery terminal.
4. Connect diagnosis connector terminals
F/P and GND with
a jumper wire.
5. Turn the ignition switch ON to operate the fuel pump.
6. Measure the pump maximum pressure.
Fuel pump maximum pressure:
441-637 kPa (4.5-6.5 kg/cm2, 64-92 psi) .--
7. Turn the ignition switch OFF and disconnect the jumper wire.
8. If not as specified, replace the fuel pump.
F-l 26

FUEL SYSTEM F
DISCONNECT CONNECTOR
TO RELEASE FU5L PRESSURE
REAR SEAT C
23UOFX-11:
REPLACE
03UOFX-14s Replacement
Warning
l Before performing the following procedures, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-121 .)
l When replacing the fuel system parts, keep sparks,
cigarettes, and open flames away from the fuel.
1. Push the rear seat cushion buttons and remove the cushion.
2. Remove the fuel pump cover.
3. Disconnect the fuel pump connector.
4. Disconnect the fuel hoses.
5. Remove the fuel pump and fuel tank gauge sender unit as-
sembly.
Caution
l Secure the fuel hoses tightly.
+ Use a new seal rubber.
6. Install in the reverse order of removal.
F-l 27

FUEL SYSTEM F
STA
OBUOFX- 15
03UOFX-15
DISCONNECT CONNECTOR
TO RELEASE FUfL PRESSURE
REAR SEAT C
23UOFX-11
INSTALL CLAMPS
CIRCUIT OPENING RELAY
Inspection
Voltage inspection
I, Check voltage between the following terminals and a ground
using a voltmeter.
Ve: Battery voltage
Resistance inspection
1, Check resistance between the terminals using an ohmmeter.
Terminal Resistance (Q)
STA-El 21-43
B-Fc 109-226
B-Fp 00
Replacement
1, Remove the passenger side wall.
2. Disconnect the relay connector.
3. Remove the relay from ECU bracket.
4. Install in the reverse order of removal.
PRESSURE REGULATOR
Inspection
Fuel line pressure
Warning
l Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-121.)
1, Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge between the fuel filter and
the fuel main hose. (Install clamps as shown.)
3. Connect the negative battery terminal.
4. Start the engine and run it at idle.
5. Measure the fuel line pressure.
Fuel line pressure:
206-255 kPa (2.1-2.6 kg/cm2, 30-37 psi)
6. Disconnect the vacuum hose from the pressure regulator
and measure the fuel line pressure.
Fuel line pressure:
265-314 kPa (2.7-3.2 kg/cm2, 36-46 psi)
F-l 29
03UOFX-157

F FUELSYSTEM
DISCONNECT CONNECTOR
TO RELEASE FlJ$L PRESSURE
REAR SEAT C
23UOFX-11
INSTALL CLAMPS 7
03UOFX.I 59
F-l 30
DIAGNOSl&OJNECTOR
/ K
1 SUOFX-10
DISCONNECT CONNECTOR
TO RELEASE
FlJl$L PRESSURE
23UOFX-11
I
Hold pressure
Perform this inspection if the fuel pressure hold inspection is
not as specified. (Refer to page F-121 .)
Warning
l Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-121 .) ,-
1. Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge between the fuel filter and
the fuel main hose. (Install clamps as shown.)
3. Connect the negative battery terminal.
4. Connect the diagnosis connector terminals
F/P and GND
with a jumper wire.
5. Turn the ignition switch ON
for 10 seconds to operate the
fuel pump.
6. Turn the ignition switch OFF and disconnect the jumper wire.
7. Pinch the fuel return hose with pliers.
8. Observe the fuel pressure
for 5 minutes.
Fuel pressure:
More than 147 kPa (1.5 kg/cm2, 21 psi)
9. If not as specified, replace the pressure regulator.
Replacement
Warning
l Before performing the followlng operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or flre. (Refer to page F-l 21.)
l When replacing fuel system components, keep
sparks, cigarettes, and open flames away from the
fuel.
1. Disconnect the vacuum hose.
2. Disconnect the fuel return hose.
3. Remove the pressure regulator.
Tightening torque:
7.8-11 N#m (80-110 cm-kg, 89-95 In-lb)
4. Install a new O-ring.
5. Install in the reverse order of removal.

231JOFX-1
FUEL SYSTEM F
INJECTOR
Inspection
Operation check
1. Warm up the engine and run it at idle.
2. Listen for operational sound of each injector with a screw-
driver or a sound scope.
3. If no sound is heard, measure injector resistance.
4. If the injector resistance is OK, check wiring to the injector
and the voltages of the ECU terminals MTX (2A, 2U and
2V) ATX (3A, 3U and 3V).
(Refer to page F-152.)
Injector resistance
1. Disconnect the injector harness.
2. Measure resistance of the injector with an ohmmeter.
Resistance: 12-l 6Q
3. If not as specified, replace the injector.
03UOFX-1
DISCONNECT CONNECTOR
TO RELEASE FU5L PRESSUR
REAR SEAT C
23UOFX-1
OBUOFX-
GRQMMET
INSULATOR
c5
OSUOFX-
Removal
Warning
l Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F-121 .)
l When removing the fuel system components, keep
sparks, cigarettes, and open flames away from the
fuel.
1. Disconnect the connectors from the injectors.
2. Remove the injector harness from the delivery pipe.
3. Remove the bolts from the intake manifold.
4. Remove the delivery pipe with the injectors and the pres-
sure regulator.
5. Remove the injectors, grommets, and insulators.
F-131

F PRESSURE REGULATOR CONTROL SYSTEM
PRESSURE REGULATOR CONTROL SYSTEM (BP ENGINE)
THERMOSEN
SOLENOID VALVE
(PRESSURE REGULATOR CONTROL)
(FROM DELIVERY
FUEL
(TO FUEL TANK)
Engine
BP SOHC
BP DOHC Coolant temperature
Above 90% (194*F) Operating condition
Intake air temperature
Above 50°C (122OF)
Above 58OC (136OF) Engine condition . Operating time (set)
Throttle valve fully closed
Approx. 120
or no load condition
Approx. 60
#.nr IAt-%/ 4 7
To prevent percolation of the fuel during hot restart idle, vacuum to the pressure regulator is momentarily
cut, and the fuel injection pressure is increased to slightly more than 284 kPa (2.9 kg/cm2, 41.2 psi).
F-l 34

EVAPORATIVE EMISSION CONTROL SYSTEM F
-l CHECK-AND-CUT VALVE
Inspection
1. Remove the check-and-cut valve.
2. Connect a pressure gauge to the passage connected to
the fuel tank.
3. Blow through the valve from port A and verify that the valve
opens at 6.36-6.34
kPa (0.065-0.065 kg/cm2,
0.92-l 2.09 psi).
4. Remove the pressure gauge and connect it to the passage
to atmosphere.
5. Blow through the valve from port B and verifyjhat the valve
opens at
0.96-4.91 kPa (0.01-0.05 kg/cmL, 0.14-0.71
psi). 1 9MUOF2-194
Note
l The test must be performed with the valve held
horizontally. Otherwise, the ball in the valve will
move out of position and close the passage.
CHARCOAL CANISTER
Inspection
1. Visually check for damage and replace the charcoal canis-
ter if necessary.
F-141

F CONTROL SYSTEM
STRUCTURAL VIEW
23UOFX-1:
1. Engine control unit (ECU) 8. Solenoid valve (Pressure regulator control)
- .--
Removal / Installation . . . . . . . . . . . . . . . . page F-149
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page F-149
2. Circuit opening relay
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . page F-l 29
Inspection ,...,........................... page F-l 29
3. Clutch switch (MTX)
inspection . . . . . . . . . . . . . . . . . . . . . . . . . page F-l 72
4. Airflow meter (With intake air thermosensor)
Inspection .,..........,...,............... page F-l 68
5. ISC valve
Inspection .,*,........,.,.........,....... page F-116
Removal / Installation . . . . . . . . ,.... page F-l 09
G-Throttle sensor
Inspection . . . . . . . . . . . . , . . . . . . page F- 169
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . page F-l 09
7. Solenoid valve (VICS) [DOHC]
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page F-l 18 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9. Water thermosensor
Inspection. . . . . . . .
Removal I Installation ....I..........
10. Solenoid valve(Purge control)
Inspection ,............ ,..................
11, Main relay (FUEL INJ relay)
Inspection. ..,............................
12. Neutral switch (MTX)
Inspection ,.,,,,....I.l,,.........I.......
Replacement . . . . . . .
13. Oxygen sensor
Inspection,. . . .
Replacement . , . . . .
14. P/S pressure switch
Inspection . . ..__.._._._........
Replacement . , . . . . . . . . . . . . . page t-135
page F-l 68
page F--l 68
page F-l 40
page F-172
page F-l 73
page F-173
page F-171
page F-172
--
page F-173
page F-173
F-l 48