Mitsubishi Galant. Manual — part 137

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-229

STEP 13. Check the sensor power supply line for short
circuit to ground at PCM connector C-40.
(1) Disconnect PCM connector C-40 and measure at the

harness side.

(2) Check for the continuity between terminal 46 and ground.

•

There should be 2 ohms or more.

Q: Does the multi-meter reading exceed the specified

value?
YES : Go to Step 26.
NO : Go to Step 14.

STEP 14. Check the sensor power supply lines.
(1) Check all the sensor power supply lines for damage, which

flow through the harness PCM connector (terminal 46).

Q: Is there any failure in the sensor power supply lines?

When a failure is found : Repair if necessary. (Refer to

GROUP 90, Circuit Diagrams

−

MFI System <2.4L

ENGINE>

P.90-30

. Then go to Step 26.)

STEP 15. Check the ground circuit voltage at PCM
connector C-40.
(1) Do not disconnect PCM connector C-40.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 57 and ground by

backprobing.

•

Voltage should be 0.5 volts or less.

(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the multi-meter reading below the specified value?

YES : Check connectors D-15, C-71, C-17, C-40 and repair

or replace as required. Refer to GROUP 00E,
Harness Connector Inspection

P.00E-2

. If connectors

D-15, C-71, C-17, C-40 are in good condition, check
the harness between intermediate connector D-15
and PCM connector C-40 for open circuit or damage.
Then repair if necessary. Then go to Step 26 .

NO : Go to Step 16.

AC004964 AB

C-40

HARNESS SIDE
CONNECTOR

AC004965 AB

C-40

HARNESS SIDE
CONNECTOR

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-230

STEP 16. Check PCM connector C-40 for damage.
(1) Disconnect PCM connector C-40.

Q: Is there any failure at PCM connector C-40?

YES : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 26.

NO : Go to Step 26.

STEP 17. Check the harness between fuel tank differential
pressure sensor connector D-11 and intermediate
connector D-15 for open circuit or damage.
(1) Disconnect fuel tank differential pressure sensor connector

D-11 and intermediate connector D-15.

Q: Is there any failure between fuel tank differential

pressure sensor connector D-11 and intermediate
connector D-15?
YES : Repair it. Then go to Step 26.
NO : Check connectors D-11, D-15 and repair or replace as

required. Refer to GROUP 00E, Harness Connector
Inspection

P.00E-2

. Then go to Step 26.

STEP 18. Check PCM connector C-41 for damage.
(1) Disconnect PCM connector C-41.

Q: Is there any failure at PCM connector C-41?

YES : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 26.

NO : Go to Step 19.

AC005043

CONNECTOR : C-40

PCM

AC

AC002041AC

CONNECTOR: D-11

FUEL TANK DIFFERENTIAL
PRESSURE SENSOR

AC002549AC

CONNECTOR: D-15

INTERMEDIATE
CONNECTOR

AC005043

CONNECTOR : C-41

PCM

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MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-231

STEP 19. Using scan tool MB991502, check data list item
73: Fuel Tank Differential Pressure Sensor.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Remove the fuel cap.
(4) Set scan tool MB991502 to the data reading mode for item

73, Fuel Tank Differential Pressure Sensor.

•

The fuel tank pressures should be -1.5 to 1.5kPa.

(5) Connect an evaporative emission system pressure pump to

the fuel filler neck, and apply pressure.

•

The scan tool reading should increase.

Q: Is the scan tool reading within the specified value?

YES : Go to Step 26.
NO : Replace the PCM. Then go to Step 26.

STEP 20. Check for clogging in the evaporator line from
hose E to hose G.
(1) Remove the module bracket mounting bolts, and

disconnect hose E from the evaporative emission
ventilation solenoid side, and plug the hoses from which the
hoses have been disconnected.

(2) Install the EVAP pressure pump outlet hose to the fuel tank

filler neck as described in the pump manufacturer's
instructions.

(3) On the EVAP pressure pump, set the pressure/hold valve to

OPEN, and set the vent valve to CLOSED.

(4) Turn the pump timer to ON. You can reset the timer as

required. (These settings are listed under "Leak Test" in the
pump instructions.)

(5) When the hose G is unplugged, the air passes through the

hose G.

Q: Does air pass through the hose E?

YES : Go to Step 21.
NO : Go to Step 23.

AC003081 AB

16 PIN

MB991502

AC000186

AC002028

HOSE E

AC

OPEN

OPEN

CLOSED

CLOSED

Pressure
Hold

Vent

ACX01806

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-232

STEP 21. Check the vent valve module for clogging.
(1) Check the rover vent valve module for clogging. (Refer to

GROUP 17

−

Vent Valve

P.17-96

.)

Q: Are there any clogs?

YES : Replace the vent valve module. Then go to Step 26.
NO : Go to Step 22.

STEP 22. Check for clogging in the evaporator line from
hose O and hose P.
(1) Carry out the clogging test with a hand vacuum pump on

each hose from hose O and hose P.

Q: Are there any clogs?

YES : Replace that hose. Then go to Step 26.
NO : Go to Step 26.

STEP 23. Check for clogging in the evaporator line from
hose G.
(1) Carry out the clogging test with a hand vacuum pump on

each hose from hose G.

Q: Are there any clogs?

YES : Replace that hose. Then go to Step 26.
NO : Go to Step 24.

AC002034 AB

AC002033 AE

HOSE P

HOSE O

AC002072

HOSE G

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