Mitsubishi Montero (2004+). Manual - part 225

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-387

STEP 9. Check harness connector B-33, B-35, B-11 at left
bank injector for damage.
Q: Is the harness connector in good condition?

YES : Then go to Step 10.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 16.

STEP 10. Check the left bank injector.
(1) Remove the intake manifold.
(2) Disconnect the left bank injector connector.

(3) Measure the resistance between injector side connector

terminal No. 1 and No. 2.

Standard value: 13

− 16 ohms [at 20°C (68°F)]

Q: Is the resistance between 13 and 16 ohms [at 20

°C

(68

°F)]?

YES : Repair harness wire between injector intermediate

connector and left bank injector connector because of
harness damage. Then go to Step 16.

NO : Replace the injector. Then go to Step 16.

AK201292

B-11(GR)

B-35(GR)

B-33(GR)

CONNECTORS: B-11, B-33, B-35

HARNESS
CONNECTORS:
COMPONENT SIDE

AK201292

B-11(GR)

B-35(GR)

B-33(GR)

CONNECTORS: B-11, B-33, B-35

HARNESS
CONNECTORS:
COMPONENT SIDE

AKX01414AB

INJECTOR SIDE
CONNECTOR

1 2

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-388

STEP 11. Check harness connector D-132 at PCM for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 12.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 16.

STEP 12. Check for harness damage between left bank
injector connector and PCM connector.

a. Check the harness wire between injector connector B-33

(terminal No. 2) and PCM connector D-132 (terminal No. 9)
at No. 2 cylinder injector.

b. Check the harness wire between injector connector B-35

(terminal No. 2) and PCM connector D-132 (terminal No. 2)
at No. 4 cylinder injector.

c. Check the harness wire between injector connector B-11

(terminal No. 2) and PCM connector D-132 (terminal No.
25) at No. 6 cylinder injector.

Q: Is the harness wire in good condition?

YES : Go to Step 13.
NO : Repair it. Then go to Step 16.

STEP 13. Check the fuel pressure.
Refer to On-vehicle Service

− Fuel Pressure Test

P.13A-995

Q: Are there any abnormalities?

YES : Repair it. Then go to Step 16.
NO : Go to Step 14.

AK200938

CONNECTOR: D-132

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-132(GR)

AK201292

B-11(GR)

B-35(GR)

B-33(GR)

CONNECTORS: B-11, B-33, B-35

HARNESS
CONNECTORS:
COMPONENT SIDE

AK200938

CONNECTOR: D-132

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-132(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-389

STEP 14. Check for entry of foreign matter (water,
kerosene, etc.) into fuel.
Q: Are there any abnormalities?

YES : Replace the fuel. Then go to Step 16.
NO : Go to Step 15.

STEP 15. Replace the left bank injector.
(1) Replace the left bank injector.
(2) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 2 −

Fuel Trim Monitor

P.13A-4

(3) Check the diagnostic trouble code (DTC).
Q: Is DTC P0174 set?

YES : Replace the PCM. Then go to Step 16.
NO : The inspection is complete.

STEP 16. 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 2 −

Fuel Trim Monitor

P.13A-4

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0174 set?

YES : Retry the troubleshooting.
NO : The inspection is complete.

DTC P0175: System too Rich (bank 2)

Fuel Trim Circuit

• Refer to DTC P0201 − P0206, Injector Circuit.

P.13A-421

CIRCUIT OPERATION

• Refer to DTC P0201 − P0206, Injector Circuit.

P.13A-421

TECHNICAL DESCRIPTION

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

trim value becomes too small.

• The PCM checks whether the fuel trim value is

within a specified range.

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

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

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

AK201292

B-11(GR)

B-35(GR)

B-33(GR)

CONNECTORS: B-11, B-33, B-35

HARNESS
CONNECTORS:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-390

DTC SET CONDITIONS

Logic Flow Chart

Check Conditions

• Under the closed loop air/fuel ratio control.

• Engine coolant temperature is higher than 77°C

(171

°F).

• Volume airflow sensor output frequency is higher

than 100 Hz.

Judgment Criteria

• Long-term fuel trim has continued to be lower

than

−12.5 percent for 5 seconds.

• Short-term fuel trim has continued to be lower

than

−7.4 percent for 5 seconds.

Check Conditions

• Under the closed loop air/fuel ratio control.

• Engine coolant temperature is higher than 77°C

(171

°F).

• Volume airflow sensor output frequency is lower

than 100 Hz.

Judgment Criteria

• Long-term fuel trim has continued to be lower

than

−12.5 percent for 5 seconds.

• Short-term fuel trim has continued to be lower

than

−12.5 percent for 5 seconds.

LRN

: LONG-TERM TRIM

: SHORT-TERM TRIM

K0 : MAXIMUM LIMIT OF LONG-TERM TRIM
K1 : MAXIMUM LIMIT OF SHORT-TERM TRIM
K2 : MINIMUM LIMIT OF LONG-TERM TRIM
K3 : MINIMUM LIMIT OF SHORT-TERM TRIM

START

MONITORING

CONDITIONS

END

YES

LRN

> K0

MALFUNCTION

GOOD

LRN

< K2

< K3

> K1

CONTINUOUS FAILURE

FOR 5secs

AK302938

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