Mitsubishi Montero Sport (2004+). Manual — part 239

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-369

STEP 7. Check for open circuit or short circuit to ground
between left bank heated oxygen sensor (rear) connector
E-48 (terminal No. 3) and PCM connector C-89 (terminal
No. 26).

NOTE: Check harness after checking intermediate connector
C-79 and E-45. If intermediate connectors are damaged, repair
or replace them. Refer to GROUP 00E, Harness Connector
Inspection

P.00E-2

. Then go to Step 12.

Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 12.
NO : Repair it. Then go to Step 12.

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

AK103914

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

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25

26

27

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29

31

32

33

34

35

1

10

AB

CONNECTOR: C-89

C-89(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-370

STEP 8. Check connector C-89 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 9.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 12.

STEP 9. Check for harness damage between MFI relay
connector C-59 (terminal No. 1) and left bank heated
oxygen sensor (rear) connector E-48 (terminal No. 1).

AK103914

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

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25

26

27

28

29

31

32

33

34

35

1

10

AB

CONNECTOR: C-89

C-89(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AK200023

2 1

3

4

CONNECTOR: C-59

AB

C-59

HARNESS
CONNECTOR:
COMPONENT
SIDE

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-371

NOTE: Check harness after checking intermediate connectors
C-14, C79 and E-45.
If intermediate connectors C-14, C79 and E-45 are damaged,
repair or replace them.
Refer to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Then go to Step12.
Q: Is the harness wire in good condition?

YES : Go to Step 10.
NO : Repair it. Then go to Step 12.

STEP 10. Check for harness damage between left bank
heated oxygen sensor (rear) connector E-48 (terminal No.
3) and PCM connector C-89 (terminal No. 26).

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

AK103914

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

AB

CONNECTOR: C-89

C-89(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-372

NOTE: Check harness after checking intermediate connectors
C-14, C79 and E-45.
If intermediate connectors C79 and E-45 are damaged, repair
or replace them.
Refer to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Then go to Step12.
Q: Is the harness wire in good condition?

YES : Go to Step 11.
NO : Repair it. Then go to Step 12.

STEP 11. Retest the system.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function OBD-II Drive Cycle

− Procedure 6 −

Other Monitor

P.13A-4

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0161 set?

YES : Replace the PCM. Then go to Step 12.
NO : It can be assumed that this malfunction is intermittent.

Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

P.00-7

.

STEP 12. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 6 −

Other Monitor

P.13A-4

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0161 set

YES : Repeat the troubleshooting.
NO : The procedure is complete.

DTC P0171: System too Lean (bank 1)

.

Fuel Trim Circuit

• Refer to DTC P0201 − P0206, Injector Cir-

cuit.

P.13A-428

.

CIRCUIT OPERATION

• Refer to DTC P0201 − P0206, Injector Cir-

cuit.

P.13A-428

.

TECHNICAL DESCRIPTION

• If a malfunction occurs in the fuel system, the fuel

trim value becomes too large.

• The PCM checks whether the fuel trim value is

within a specified range.

.

DESCRIPTIONS OF MONITOR METHODS
Right bank air/fuel learning value (long time fuel trim)

and air/fuel feedback integral value (short time
fuel trim) are too lean.

.

MONITOR EXECUTION
Continuous

.

MONITOR EXECUTION CONDITIONS (Other
monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Misfire monitor

Sensor (The sensor below is determined to be

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

.