1992 MAZDA PROTEGE engine

PRESSUREREGULATORCONTROLSYSTEM F
03UOFX-17
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OSUOFX-17
SOLENOID VALVE (PRESSURE REGULATOR CONTROL)
Inspection
On-vehicle
1. Start the engine and run it at idle.
2. Disconnect the vacuum hose (Orange) from the pressure
regulator. Verify that vacuum is felt.
3. Ground the solenoid valve terminal-wire G/O with a jumper
wire. Verify that no vacuum is felt.
4. If vacuum exists, check the solenoid valve.
Solenoid Valve
1. Disconnect the vacuum hose from the solenoid valve and
vacuum pipe.
2. Blow through the solenoid valve from port @
3. Verify that air flows from port @.
4. Disconnect the solenoid valve connector.
5. Connect battery voltage and a ground to the terminals of
the solenoid valve.
6. Blow through the solenoid valve from the port @.
7. Verify that air flows from the valve air filter.
8. If not as specified, replace the solenoid valve.
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F POSITIVE CRANKCASE VENTILATION (PCV) SYSTEM
POSITIVE CRANKCASE VENTILATION (PCV) SYSTEM
DESCRIPTION
The PCV valve is operated by the intake manifold vacuum.
When the engine is running at idle, the PCV valve is opened slightly and a small amount of blowby gas
is drawn into the dynamic chamber to be burned.
As the engine speed rises the PCV valve is opened further, allowing a larger amount of blowby gas to be
drawn into the dynamic chamber.
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9MUOF2-164
PCV VALVE
Inspection
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1. Warm up the engine to the normal operating temperature
and run it at idle.
2. Disconnect the PCV valve with the ventilation hose from the
cylinder head cover,
3. Block the PCV valve opening.
4. Verify that there is vacuum.
5. Remove the PCV valve.
6. Blow through the valve from port @ and verify that air
comes out of port @I.
7. Blow through the valve from port @ and verify that no air
comes out of port @.
8. Replace the PCV valve if necessary.

EVAPORATIVE EMISSION CONTROL SYSTEM t
EVAPORATIVE EMISSION CONTROL SYSTEM
DESCRIPTION
/ /
ENGINE ENGINE
CONTROL CONTROL - INPUT - INPUT
UNIT UNIT
- -
SOLENOID VALVE SOLENOID VALVE k k / /
CHECK VALVE CHECK VALVE
(TWO-WAY) (TWO-WAY)
CHARCOAL CHARCOAL
CANISTER CANISTER
CHECK-AND-CUTC CHECK-AND-CUTC
VALVE VALVE
SEPARATOR SEPARATOR TO ENGINE TO ENGINE SIGNALS
The evaporative emission control system consists of the separator, the check-and-cut valve, the two-way
check valve, the charcoal canister, the purge control solenoid valve, the engine control unit (ECU), and the
input devices. The amount of evaporative fumes introduced into the engine and burned is controlled by the
solenoid valve to correspond to the engine’s operating conditions. To maintain best engine performance,
the solenoid valve is controlled by the ECU.
Operation
.._ The solenoid valve (purge control) is controlled by duty signals from the ECU to perform purging of the char-
coal canister. Purging is done when these conditions are met:
(1) After warm-up
(2) Driving in gear
(3) Accelerator pedal depressed (idle switch OFF)
(4) Oxygen sensor functioning normally
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F EVAPORATIVE EMISSION CONTROL SYSTEM
03UOFX-17! 3
03UOFX-180
INSTALLATION DIRECTION
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I
23UOFX-126
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OSUOFX-l&
SYSTEM OPERATION
1 Warm up the engine to normal operating temperature and
run it at idle.
2. Disconnect the vacuum hose from the solenoid valve as
shown in the figure, and verify that no vacuum is felt at the
solenoid valve. -.
3. If not as specified, check the solenoid valve.
SOLENOID VALVE (PURGE CONTROL)
Inspection
1. Disconnect the vacuum hoses from the solenoid valve.
2. Verify that no air flows through the valve.
3. Disconnect the solenoid valve connector and supply bat-
tery voltage as shown in the figure.
4. Verify that air flows through the valve.
5. If not as specified, replace the solenoid valve.
SEPARATOR
Inspection
1. Remove the left side trim.
2. Remove the separator.
3. Visually check the separator for damage. Replace it if
necessary.
CHECK VALVE (TWO-WAY)
Inspection
1. Remove the valve.
2. Check the operation of the valve with a vacuum pump.
Apply approx. 37 mmHg (1.46 inHg)
vacuum at port A Airflow
Apply approx. 44 mmHg (1.73 inHg)
vacuum at port B Airflow

F DECELERATION CONTROL SYSTEM
DECELERATION CONTROL SYSTEM
DESCRIPTION
The dashpot is used to prevent the throttle valve from suddenly closing
03UOFX-185
1
DASHPOT
Inspection
1. Open the throttle valve fully. Push the dashpot rod with a
finger and verify that it goes into the dashpot slowly.
2. Release the rod and check that it comes out quickly.
3. Replace the dashpot if not as specified.
,,
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4. Warm up the engine and run it at idle.
5. Connect a tachometer to the diagnosis connector IG-
terminal and increase engine speed to 4,000 rpm.
6. Slowly decrease the engine speed and check that the le-
ver touches the dashpot rod at the specified speed.
Specification:
l B6 ..**.............,....,.............. Approx. 3,000 rpm
l BP SOHC . ..*..................*.... Approx. 2,700 rpm
l BP DOHC . . . . . . . . . . . . . . . . . . . . ...“... Approx. 3,500 rpm
7. If not as specified, loosen the locknut and turn the dashpot
to adjust.
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FUEL CUT CONTROL SYSTEM F
FUEL CUT CONTROL SYSTEM
DESCRIPTION
This system is used to improve the fuel economy, to prevent engine bucking during deceleration, and to
protect the engine from overspeeding.
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PREPARATION
SST
r
49 9200 162
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l7=---T II USE CPNNECTOR A
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SYSTEM OPERATION
1. Connect a tachometer to the diagnosis connector IG-
terminal.
2. Connect the
SSTs (Engine Signal Monitor and Adapt-
er)
to the engine control unit (ECU).
3. Warm-up the engine to normal operating temperature and
run it at idle.
Warning
l Confirm that transmission is in Neutral (MTX) or P
range (ATX).
4.
Set the SST (Sheet) on the Engine Signal Monitor with
the specified side fancing up as shown.
Note
l MTX...48 PIN
l ATX...64 PIN
I 23UOFX-128
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F FUEL
23UOFX-12:
0-6V
23UOFX- 131
to the terminal 2U or 2V (MTX), 3U or 3V (ATX)
hat the green and red lamps flash alternately.
nd No,3.....ECU terminal 2U (MTX)
3U (ATX)
. . . ..ECU terminal 2V (MTX)
3V (ATX)
6. Increase the engine speed to 4,000 rpm and then suddenly
release the throttle.
7. Verify that the red indicator lamp illuminates while the en-
gine speed is above approx.
1,900 rpm on deceleration.
t aced maximum rpm over 3 sec.
8. Increase the engine speed and verify that the maximum rpm
does not exceed specification.
.
.
. ..“.*..1”*“.-.“.....*......*...
Approx. 7,300 rpm
. . ..I......m....“.....*........m Approx. 6,300 rpm
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DECHOKE CONTROL SYSTEM t-
DECHOKE CONTROL SYSTEM
DESCRIPTION
To facilitate starting the engine when the spark plugs become fouled, such as when the engine is flooded,
fuel injection is cut if the throttle valve is held wide open while cranking and the engine coolant temperature
is O°C (32OF) or below. This allows the spark oluas to drv and purges excess fuel from the cylinders.
f-- ECU _
. IGNITION SWITCH (START)
l ENGINE SPEED BELOW 500 rpm ’
l THROTTLE VALVE FULLY OPEN
l ENGINE COOLANT TEMPERATURE ;
BELOW
0% (32°F) I FUEL CUT
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I / / ‘ I
SYSTEM OPERATION
1.
2. Check if the engine coolant temperature is below O°C
(32OF).
If the engine coolant temperature is above O°C (32OF), dis-
connect the water thermosensor connector and connect an
approx. 10 kB resistor to the connector.
03UOFX.198 3. Turn the ignition switch to START and verify that the injec-
OBUOFX-19! 3
tor operating sound is heard.
4. Depress the accelerator pedal fully and turn the ignition
switch START. Verify that no injector operating sound is
heard.
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