Mitsubishi 380. Manual - part 620

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI) <3.8L ENGINE>

13A-572

STEP 2. Using diagnostic tool, check data list.

CAUTION

To prevent damage to diagnostic tool, always turn the igni-
tion switch to the "LOCK" (OFF) position before connect-
ing or disconnecting diagnostic tool.
(1) Connect diagnostic tool to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check the following item in the data list. Refer to Data List 

Reference Table 

P.13A-637

.

a. Item 6: Engine Coolant Temperature Sensor.

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

Q: Is the sensor operating properly?

YES : Go to Step 3.
NO :  Repair or replace it. Then confirm that the malfunction 

symptom is eliminated.

STEP 3. Using diagnostic tool, check actuator test.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following item in the actuator test. Refer to 

Actuator Test Reference Table 

P.13A-644

.

a. Item 10: Evaporative Emission Purge Solenoid.

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

Q: Is the actuator operating properly?

YES : Refer to On-vehicle Service 

− Throttle Body (Throttle 

Valve Area) Cleaning. 

P.13A-660

.

NO :  Repair or replace it. Then confirm that the malfunction 

symptom is eliminated.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI) <3.8L ENGINE>

13A-573

INSPECTION PROCEDURE 10: Idle Speed Is Low (Improper Idle Speed).

.

COMMENT

• In cases such as the above, the cause is proba-

bly that the intake air volume during idle is too 
small.

.

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

• Malfunction of the electronic control throttle valve 

system.

• Malfunction of the throttle body.

• Refer to component locations GROUP-

70

• Refer to configuration diagrams GROUP-

80

• Refer to circuit diagrams GROUP-

90

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

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

CAUTION

To prevent damage to diagnostic tool, always turn the igni-
tion switch to the "LOCK" (OFF) position before connect-
ing or disconnecting diagnostic tool.
(1) Connect diagnostic tool 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 the DTC set?

YES : Refer to Diagnostic Trouble Code Chart 

P.13A-17

.

NO :  Go to Step 2.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI) <3.8L ENGINE>

13A-574

STEP 2. Using diagnostic tool, check data list.

CAUTION

To prevent damage to diagnostic tool, always turn the igni-
tion switch to the "LOCK" (OFF) position before connect-
ing or disconnecting diagnostic tool.
(1) Connect diagnostic tool to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check the following item in the data list. Refer to Data List 

Reference Table 

P.13A-637

.

a. Item 6: Engine Coolant Temperature Sensor.

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

Q:  Is the sensor operating properly?

YES : Refer to On-vehicle Service 

− Clean the throttle valve 

area 

P.13A-660

.

NO :  Repair or replace it. Then confirm that the malfunction 

symptom is eliminated.

INSPECTION PROCEDURE 11: When the engine is cold, it stalls at idle (die out).

.

COMMENT

• In such cases as the above, the air/fuel mixture 

may be inappropriate when the engine is cold.

.

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

• Malfunction of the electronic control throttle valve 

system.

• Malfunction of the throttle body.

• Malfunction of the injector system.

• Malfunction of the ignition system.

• Refer to component locations GROUP-

70

• Refer to configuration diagrams GROUP-

80

• Refer to circuit diagrams GROUP-

90

DIAGNOSIS

Required Special Tools:

• Diagnostic tool(MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

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.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI) <3.8L ENGINE>

13A-575

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

CAUTION

To prevent damage to diagnostic tool, always turn the igni-
tion switch to the "LOCK" (OFF) position before connect-
ing or disconnecting diagnostic tool.
(1) Connect diagnostic tool 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 the DTC set?

YES : Refer to Diagnostic Trouble Code Chart 

P.13A-17

.

NO :  Go to Step 3.

STEP 3. Checking by operating the accelerator pedal.

Q: Does the engine stall right after the accelerator pedal is 

released?
YES : Refer to GROUP13B, On-vehicle Service 

− Throttle 

Body (Throttle Valve Area) Cleaning. 

P.13A-660

.

NO :  Go to Step 4.

STEP 4. Check the engine idling.

Q: Is the idling good enough after warm up?

YES : Go to Step 5.
NO :  Refer to INSPECTION PROCEDURE 8 

− Unstable 

Idle (Rough Idle, Hunting) 

P.13A-566

.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827