Mitsubishi Montero (2004+). Manual - part 224

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-383

• 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 higher 

than +12.5 percent for 5 seconds.

or

• Short-term fuel trim has continued to be higher 

than +12.5 percent for 5 seconds.

Check Conditions

• Engine coolant temperature is higher than 

approximately 100

°C (212°F) when the engine is 

started.

• Intake air temperature is higher than 60°C 

(140

°F) when the engine is started.

• 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 higher 

than +12.5 percent for 5 seconds.

or

• Short-term fuel trim has continued to be higher 

than +17.6 percent for 5 seconds.

Check Conditions

• Engine coolant temperature is higher than 

approximately 100

°C (212°F) when the engine is 

started.

• Intake air temperature is higher than 60°C 

(140

°F) when the engine is started.

• 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 higher 

than +12.5 percent for 5 seconds.

or

• Short-term fuel trim has continued to be higher 

than +22.3 percent for 5 seconds.

Check Conditions

• Engine coolant temperature is higher than 77°C 

(171

°F).

• Under the closed loop air/fuel ratio control.

Judgment Criteria

• Long-term fuel trim has continued to be +12.5 

percent for 5 seconds.

or

• Short-term fuel trim has continued to be +25.0 

percent for 5 seconds.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 2 

− Fuel Trim Monitor 

P.13A-4

.

.

TROUBLESHOOTING HINTS (The most likely 

causes for this code to be set are: )

• Volume airflow sensor failed.

• Injector (Number 2, 4, 6) failed.

• Incorrect fuel pressure.

• Air drawn in from gaps in gasket, seals, etc.

• Engine coolant temperature sensor failed.

• Intake air temperature sensor failed.

• Barometric pressure sensor failed.

• Exhaust leak.

• Use of incorrect or contaminated fuel.

• Harness damage in left bank injector circuit or 

connector damage.

• PCM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Check the exhaust leaks.
Q: Are there any abnormalities?

YES : Go to Step 2.
NO :  Repair it. Then go to Step 16.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-384

STEP 2. Check the intake system vacuum leak.
Q: Are there any abnormalities?

YES : Go to Step 3.
NO :  Repair it. Then go to Step 16.

STEP 3. Using scan tool MB991958, check data list item 12: 
Volume Airflow Sensor.

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.

(3) Set scan tool MB991958 to the data reading mode for item 

12, Volume Airflow Sensor.

(4) Warm up the engine to normal operating temperature: 80

°C 

to 95

°C (176°F to 203°F).

• When idling, between 17 and 43 Hz (between 3.5 and 

7.5 gm/s).

• When 2,500 r/min, between 64 and 104 Hz (between 

13.6 and 19.6 gm/s).

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : YES: Go to Step 4.
NO :  Refer to DTC P0101 

− Volume Airflow Circuit 

Range/Performance Problem 

P.13A-33

, DTC P0102 

− Volume Airflow Circuit Low Input 

P.13A-42

.

STEP 4. Using scan tool MB991958, check data list item 13: 
Intake Air Temperature Sensor.

(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool MB991958 to the data reading mode for item 

13, Intake Air Temperature Sensor.

• The intake air temperature and temperature shown with 

the scan tool should approximately match.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Go to Step 5.
NO :  Refer to DTC P0111 

− Intake Air Temperature Circuit 

Range/Performance Problem 

P.13A-95

, DTC P0112 

− Intake Air Temperature Circuit Low Input 

P.13A-102

, DTC P0113 

− Intake Air Temperature 

Circuit High Input 

P.13A-107

.

AK302970

AB

MB991911

MB991824

MB991827

AK302970

AB

MB991911

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-385

STEP 5. Using scan tool MB991958, check data list item 21: 
Engine Coolant Temperature Sensor.

(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool MB991958 to the data reading mode for item 

21, Engine Coolant Temperature Sensor.

• The engine coolant temperature and temperature 

shown with the scan tool should approximately match.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Go to Step 6.
NO :  Refer to DTC P0116 

− Engine Coolant Temperature 

Circuit Range/Performance Problem 

P.13A-114

, DTC 

P0117 

− Engine Coolant Temperature Circuit Low 

Input 

P.13A-125

, DTC P0118 

− Engine Coolant 

Temperature Circuit High Input 

P.13A-130

.

STEP 6. Using scan tool MB991958, check data list item 25: 
Barometric Pressure Sensor.

(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool MB991958 to the data reading mode for item 

25, Barometric Pressure Sensor.

• When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg.).

• When altitude is 600 m (1,969 feet), 95 kPa (28.1 

in.Hg.).

• When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 

in.Hg.).

• When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 

in.Hg.).

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Go to Step 7.
NO :  Refer to DTC P2227 

− Barometric Pressure Circuit 

Range/Performance Problem 

P.13A-802

,  DTC 

P2228 

− Barometric Pressure Circuit Low Input 

P.13A-808

, DTC P2229 

− Barometric Pressure Circuit 

High Input 

P.13A-822

.

AK302970

AB

MB991911

MB991824

MB991827

AK302970

AB

MB991911

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-386

STEP 7. Check harness connector B-44 at injector 
intermediate connector for damage.

Q: Is the harness connector in good condition?

YES : Go to Step 8.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 16.

STEP 8. Check the left bank injector resistance at 
intermediate connector B-44.
(1) Disconnect the injector intermediate connector B-44.

(2) Measure the resistance between each injector side 

connector terminal.

a. Measure the resistance between terminal No. 8 and No. 

2 at No. 2 cylinder injector.

b. Measure the resistance between terminal No. 8 and No. 

7 at No. 4 cylinder injector.

c. Measure the resistance between terminal No. 8 and No. 

5 at No. 6 cylinder injector.

• Resistance should be between 13 and 16 ohms

[at 20

°C (68°F)].

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

20

°C (68°F)]?

YES : Go to Step 11.
NO :  Go to Step 9.

AK200949

3

4

7

8

1

2

5

6

B-44(B)

CONNECTOR: B-44

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

AK200949

3

4

7

8

1

2

5

6

B-44(B)

CONNECTOR: B-44

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

AK000533

6

3 4
7 8

1 2
5

AK000533

6

3 4
7 8

1 2
5

INJECTOR
INTERMEDIATE
CONNECTOR

AB