Mitsubishi Montero Sport (2004+). Manual — part 338

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-765

STEP 10. Check the fuel pressure.
Refer to On-vehicle Service

− Fuel Pressure Test

P.13A-884

.

Q: Is the fuel pressure normal?

YES : Go to Step 11.
NO : Repair or replace. Then confirm that the malfunction

symptom is eliminated.

STEP 11. Using scan tool MB991958, check data list.

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) Turn the ignition switch to the "ON" position.
(3) Check the following items in the data list. Refer to Data List

Reference Table

P.13A-839

.

a. Item 45: Idle Air Control Motor Position.

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

YES : Check the following items, and repair or replace the

defective items.

a. Vacuum leak.

• Broken intake manifold gasket.

• Broken air intake hose.

• Broken vacuum hose.

• Positive crankcase ventilation valve does

not operate.

b. Injector clogged.

Then confirm that the malfunction symptom is

eliminated.

NO : Adjusting the basic idle speed. Refer to On-vehicle

Service

− Basic Idle Speed Adjustment

P.13A-883

.

STEP 12. Check the ignition timing.
Refer to GROUP 11A, On-vehicle Service

− Ignition Timing

Check

P.11A-9

.

Q: Is the ignition timing normal?

YES : Check the following items, and repair or replace the

defective items.

a. Check the ignition coil, spark plugs, spark plug

cables.

b. Check if the injectors are clogged.

c. Check compression pressure.

d. Check if the foreign materials (water,

kerosene, etc.) got into fuel.

Then confirm that the malfunction symptom is

eliminated.

NO : Check that the crankshaft position sensor and timing

cover are in the correct position. Then confirm that the
malfunction symptom is eliminated.

AK303629AB

MB991911

MB991827

MB991824

16-PIN

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-766

INSPECTION PROCEDURE 13: The Engine Stalls when Accelerating (Pass Out).

.

COMMENT

• In case such as the above, the cause is probably

misfiring due to a weak spark, or an inappropriate
air/fuel mixture when the accelerator pedal.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case: )

• Vacuum leak.

• Malfunction of the ignition system.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Using scan tool MB991958, read the diagnostic
trouble code (DTC).

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) Turn the ignition switch to the "ON" position.
(3) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC set?

YES : Refer to Diagnostic Trouble Code Chart

P.13A-26

.

NO : Go to Step 2.

AK303629AB

MB991911

MB991827

MB991824

16-PIN

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-767

STEP 2. Using scan tool MB991958, check actuator test.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items in the actuator test. Refer to

Actuator Test Reference Table

P.13A-854

.

a. Item 10: EGR Vacuum Regulator Solenoid Valve.

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

YES : Check the following items, and repair or replace the

defective items.

a. Check the ignition coil, spark plugs, spark plug

cables.

b. Check for vacuum leaks.

• Broken intake manifold gasket.

• Broken or disconnected vacuum hose.

• Improper operation of the PCV valve.

• Broken air intake hose.

Then confirm that the malfunction symptom is

eliminated.

NO : Repair or replace. Then confirm that the malfunction

symptom is eliminated.

INSPECTION PROCEDURE 14: The engine stalls when decelerating.

.

COMMENT

• The intake air volume may be insufficient due to a

defective idle air control motor system.

.

TROUBLESHOOTING HINTS (The most likely
causes for this case: )

• Malfunction of the IAC system.

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 if the battery terminal is disconnected
Q: Has the battery terminal been disconnected lately?

YES : Start the engine and let it run at idle for approximate

10 minutes after engine warm up. Then if a
malfunction occurs, go to step 2.

NO : Go to Step 2.

AK303629AB

MB991911

MB991827

MB991824

16-PIN

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-768

STEP 2. Using scan tool MB991958, read the diagnostic
trouble code (DTC).

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) Turn the ignition switch to the "ON" position.
(3) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC set?

YES : Refer to Diagnostic Trouble Code Chart

P.13A-26

.

NO : Go to Step 3.

STEP 3. Using scan tool MB991958, check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items in the data list. Refer to Data List

Reference Table

P.13A-839

.

a. Item 14: Throttle Position Sensor.

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

YES : Go to Step 4.
NO : Repair or replace. Then confirm that the malfunction

symptom is eliminated.

AK303629AB

MB991911

MB991827

MB991824

16-PIN

AK303629AB

MB991911

MB991827

MB991824

16-PIN