Mitsubishi Galant (2004+). Manual — part 1186

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-437

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 −30.0

percent for 5 seconds.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 2

− Fuel Trim Monitor

P.13B-5

.

.

TROUBLESHOOTING HINTS (The most likely

causes for this code to be set are:)

• Mass airflow sensor failed.

• Injector (Number 2, 4, 6) failed.

• Incorrect fuel pressure.

• Engine coolant temperature sensor failed.

• Intake air temperature sensor failed.

• Barometric pressure sensor failed.

• Manifold absolute pressure sensor failed.

• 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

• MB991910: Main Harness A

STEP 1. Using scan tool MB991958, check data list item 12:
Mass 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, Mass Airflow Sensor.

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

°C

to 95

°C (176°F to 203°F).

• When idling, between 2.0 and 6.0 g/sec.

• When 2,500 r/min, between 8.0 and 16.0 g/sec.

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

YES : YES: Go to Step 2.
NO : Refer to, DTC P0101

− Mass Airflow Circuit

Range/Performance Problem

P.13B-40

, DTC P0102

− Mass Airflow Circuit Low Input

P.13B-51

, DTC

P0103

− Mass Airflow Circuit High Input

P.13B-61

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-438

STEP 2. 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 3.
NO : Refer to DTC P0111

− Intake Air Temperature Circuit

Range/Performance Problem

P.13B-103

DTC P0112

− Intake Air Temperature Circuit Low Input

P.13B-112

, DTC P0113

− Intake Air Temperature

Circuit High Input

P.13B-119

.

STEP 3. 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 4.
NO : Refer to DTC P0116

− Engine Coolant Temperature

Circuit Range/Performance Problem

P.13B-129

, DTC

P0117

− Engine Coolant Temperature Circuit Low

Input

P.13B-138

, DTC P0118

− Engine Coolant

Temperature Circuit High Input

P.13B-145

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-439

STEP 4. 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 5.
NO : Refer to DTC P2227

− Barometric Pressure Circuit

Range/Performance Problem

P.13B-943

, DTC P2228

− Barometric Pressure Circuit Low Input

P.13B-945

,

DTC P2229

− Barometric Pressure Circuit High Input

P.13B-947

.

STEP 5. Using scan tool MB991958, check data list item 95:
Manifold Absolute Pressure Sensor.

(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

95, Manifold Absolute 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).

(4) Start the engine.

• When the engine is idling, 16 − 36 kPa (4.7 − 10.6

in.Hg).

• When the engine is suddenly revved, manifold absolute

pressure varies.

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

YES : Go to Step 6.
NO : Refer to DTC P0106

− Manifold Absolute Pressure

Circuit Range / Performance Problem

P.13B-68

, DTC

P0107

− Manifold Absolute Pressure Circuit Low

Input

P.13B-82

, DTC P0108

−Manifold Absolute

Pressure Circuit High Input

P.13B-94

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-440

STEP 6. Check the left bank injector.

(1) Disconnect the left bank injector connector B-30, B-27 ,

B-26.

(2) Measure the resistance between each injector side

connector terminal No. 1 and No. 2.

Standard value: 10.5

− 13.5 ohms [at 20°C (68°F)]

Q: Is the measured resistance between 10.5 and 13.5 ohms

[at 20

°C (68°F)]?

YES : Go to Step 7.
NO : Replace the injector. Then go to Step 9.

STEP 7. Check the fuel pressure.

Refer to On-vehicle Service

− Fuel Pressure Test

P.13B-1133

.

Q: Is the fuel pressure normal?

YES : Repair it. Then go to Step 9.
NO : Go to Step 8.

STEP 8. Replace the left bank injector.

(1) Replace the left bank injector.
(2) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 2 −

Fuel Trim Monitor

P.13B-5

.

(3) Check the diagnostic trouble code (DTC).
Q: Is DTC P0175 set?

YES : Replace the PCM. Then go to Step 9.
NO : The inspection is complete.

AK303075

M

1

2

CONNECTOR: B-26, B-27, B-30

B-30 (GR)

B-27 (GR)

B-26 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB

AK000559

2

1

INJECTOR SIDE
CONNECTOR

AB

AK303075

M

1

2

CONNECTOR: B-26, B-27, B-30

B-30 (GR)

B-27 (GR)

B-26 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB