Mitsubishi Eclipse. Manual - part 326

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-797

STEP 6. Using scan tool MB991958, check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items of data list. Refer to, Data List 

Reference Table 

P.13A-892

.

a. Item 11: Heated Oxygen Sensor (front).

• Voltage should fluctuate between 0 − 0.4 volt and 0.6 − 

1.0 volt while idling after the engine has warmed-up.

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

YES : Go to Step 8.
NO :  Go to Step 7.

STEP 7. Check the fuel pressure.
Refer to, Fuel Pressure Test 

P.13A-929

.

Q: Is the fuel pressure normal?

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 :  Repair or replace. Then confirm that the malfunction 

symptom is eliminated.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-798

STEP 8. Check the fuel pressure.
Refer to, Fuel Pressure Test 

P.13A-929

.

Q: Is the fuel pressure 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 the EGR system.

c. Check compression pressure.

d. Check the fuel filter or fuel line for clogging.

Then confirm that the malfunction symptom is 

eliminated.

NO :  Repair or replace. Then confirm that the malfunction 

symptom is eliminated.

INSPECTION PROCEDURE 16: Acceleration shock.

.

COMMENT

• There may be an ignition leak accompanying the 

increase in the spark plug demand voltage during 
acceleration.

.

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

• Malfunction of the ignition system.

DIAGNOSIS

Required Special Tools:

• MB991958 (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-799

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-24

.

NO :  Check the following items, and repair or replace the 

defective items.

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

cables.

b. Check for occurrence of ignition leak.

Then confirm that the malfunction symptom is 

eliminated.

INSPECTION PROCEDURE 17: Deceleration Shock

.

COMMENT

• There may be a sudden change in air flow 

through the IAC, causing the vehicle to deceler-
ate rapidly for an instant.

.

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

• Malfunction of the IAC system.

DIAGNOSIS

Required Special Tools:

• MB991958 (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-800

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-24

.

NO :  Go To Step 2.

STEP 2. Check the idle air control (IAC) motor operation 
sound.
(1) Check that the engine coolant temperature is 20

°C (68°F) 

or below.
NOTE: If necessary, you can disconnect the engine coolant 
temperature sensor connector and connect the harness 
side of the connector to another engine coolant temperature 
sensor that is at 20

°

C (68

°

F) or below.

(2) Check the operation sound of the IAC motor can be heard 

after the ignition is switched to the "ON" position (but 
without starting the engine).

• An operation sound should heard.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Did you hear the operation sound?

YES : Go to Step 3.
NO :  Refer to, DTC P0506 

− Idle Control System RPM 

Lower Than Expected 

P.13A-625

, DTC P0507 

− Idle 

Control System RPM Higher Than Expected 

P.13A-640

.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

AK300408

1

2

3

4

5

6

CONNECTOR: B-34

AB

B-34 (B)

HARNESS CONNECTOR:
COMPONENT SIDE