Mitsubishi Evolution X. Manual — part 297

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-165

DTC SET CONDITIONS
Logic Flow Chart

Check Condition

• Engine coolant temperature was 7° C (45° F) or

more when the engine started.

Judgement Criteria

• Engine coolant temperature fluctuates within 1° C

(1.8

° F) after 5 minutes have passed since the

engine was started.

• However, time is not counted if any of the follow-

ing conditions are met.

1. Intake air temperature is 60

° C (140° F) or

more.

2. Mass airflow sensor outputs is 10 g/sec or

less.

3. During fuel shut-off operation.

FAIL-SAFE AND BACKUP FUNCTION

• Control as if the engine coolant temperature is 80

° C.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function

− OBD-II Drive Cycle −

Pattern 8

P.13A-9

Start

End

Yes

Malfunction

Good

300secs have passed?

|dt| < 1˚C (1.8˚F)

Monitoring conditions

Start measuring the minimum and maximum

temperature from engine start

Calculate the difference of the minimum and

the maximum temperature from engine start;dt

Yes

AK703879

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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TROUBLESHOOTING HINTS (The most
likely causes for this code to be set are:)

• Engine coolant temperature sensor failed.

• Harness damage or connector damage.

• ECM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Using scan tool MB991958, check data list item 6:
Engine Coolant Temperature 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) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to the data reading mode for item

6, Engine Coolant Temperature Sensor.

• The engine coolant temperature and temperature

shown with the scan tool should approximately match.

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

YES : It can be assumed that this malfunction is intermittent.

Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

− How to

Cope with Intermittent Malfunctions

P.00-15

NO : Go to Step 2.

STEP 2. Check the engine coolant temperature sensor.
Refer to Engine Coolant Temperature Sensor Check

P.13A-907

Q: Is the engine coolant temperature sensor normal?

YES : Go to Step 3.
NO : Replace the engine coolant temperature sensor. Then

go to Step 9.

STEP 3. Check harness connector B-08 at the engine
coolant temperature sensor for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 4.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 9.

AC608435

Data link connector

MB991827

MB991824

MB991910

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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STEP 4. Check the continuity at engine coolant
temperature sensor harness side connector B-08.
(1) Disconnect the connector B-08 and measure at the harness

side.

(2) Check for the continuity between terminal No. 2 and

ground.

• Continuity (2 ohms or less)

Q: Does continuity exist?

YES : Go to Step 7.
NO : Go to Step 5.

STEP 5. Check harness connector B-09 at ECM for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 6.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 9.

STEP 6. Check for harness damage between engine
coolant temperature sensor connector B-08 (terminal No.
2) and ECM connector B-09 (terminal No. 27).
Q: Is the harness wire in good condition?

YES : Replace the ECM. When the ECM is replaced,

P.42B-12

or GROUP 42C, ID Codes

Registration Judgment Table <Vehicles with WCM>

P.42C-9

. Then go to Step 9.

NO : Repair it. Then go to Step 9.

STEP 7. Check harness connector B-09 at ECM 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 9.

AK604180

B-08 harness
connector:
component side

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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STEP 8. Check for harness damage between engine
coolant temperature sensor connector B-08 (terminal No.
1) and ECM connector B-09 (terminal No. 26).
Q: Is the harness wire in good condition?

YES : Replace the ECM. When the ECM is replaced,

P.42B-12

or GROUP 42C, ID Codes

Registration Judgment Table <Vehicles with WCM>

P.42C-9

. Then go to Step 9.

NO : Repair it. Then go to Step 9.

STEP 9. 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 − Pattern 8

P.13A-9

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0116 set?