Mitsubishi Galant 9G. Manual — part 744

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-418

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.13A-107

, DTC P0112

− Intake Air Temperature Circuit Low Input

P.13A-116

, DTC P0113

− Intake Air Temperature

Circuit High Input

P.13A-123

.

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.13A-133

, DTC

P0117

− Engine Coolant Temperature Circuit Low

Input

P.13A-142

, DTC P0118

− Engine Coolant

Temperature Circuit High Input

P.13A-149

.

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-419

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 P2228

− Barometric Pressure Circuit

Low Input

P.13A-947

, DTC P2229

− Barometric

Pressure Circuit High Input

P.13A-949

.

STEP 5. Using scan tool MB991958, check data list item 95:
Manifold Absolute Pressure Sensor.
(1) Turn the ignition switch to the "ON" position.
(2) 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).

(3) 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.

(4) 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.13A-72

, DTC

P0107

− Manifold Absolute Pressure Circuit Low

Input

P.13A-86

, DTC P0108

− Manifold Absolute

Pressure Circuit High Input

P.13A-98

.

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-420

STEP 6. Check the cylinder 1, 4 injector.
(1) Disconnect the cylinder 1, 4 injector connector B-01, B-27.

(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.13A-1124

.

Q: Is the fuel pressure normal?

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

STEP 8. Replace the cylinder 1, 4 injector.
(1) Replace the cylinder 1, 4 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.13A-6

.

(3) Check the diagnostic trouble code (DTC).
Q: Is DTC P0172 set?

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

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 − Procedure 2 −

Fuel Trim Monitor

P.13A-6

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0172 set?

YES : Retry the troubleshooting.
NO : The inspection is complete.

M

1

2

AK303822

B-01 (GR)

B-27 (GR)

CONNECTORS: B-01, B-27

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AK000559

2

1

INJECTOR SIDE
CONNECTOR

AB

M

1

2

AK303822

B-01 (GR)

B-27 (GR)

CONNECTORS: B-01, B-27

AB

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-421

DTC P0174: System too Lean (cylinder 2, 3)

CAUTION

If DTC P0174 has been set, TCL related DTC
U1120 is also set. After P0174 has been diag-
nosed, don't forget to erase DTC U1120.

.

Fuel Trim Circuit

• Refer to DTC P0202 − Injector Circuit-cylinder 2

P.13A-474

, DTC P0203

− Injector Circuit-cylinder

3

P.13A-484

.

.

CIRCUIT OPERATION

• Refer to DTC P0202 − Injector Circuit-cylinder 2

P.13A-474

, DTC P0203

− Injector Circuit-cylinder

3

P.13A-484

.

.

TECHNICAL DESCRIPTION

• If a malfunction occurs in the fuel system, the fuel

trim value becomes too large.

• The PCM checks whether the fuel trim value is

within a specified range.

.

DESCRIPTIONS OF MONITOR METHODS

Cylinder 2, 3 air/fuel learning value (long time fuel

trim) and air/fuel feedback integral value (short
time fuel trim) are too lean.

.

MONITOR EXECUTION

Continuous

.

MONITOR EXECUTION CONDITIONS
(Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Misfire monitor

Sensor (The sensor below is determined to be

normal)

• Mass airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

.