Mitsubishi Galant. Manual — part 164

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-337

STEP 5. Check the idle air control (IAC) motor operation
sound.
(1) Check that the engine coolant temperature is 20

°

C (68

°

F)

or below.

NOTE: Disconnecting the engine coolant temperature
sensor connector and connecting the harness side of the
connector to another engine coolant temperature sensor
that is at 20

°

C (68

°

F) or below is also okay.

(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 is heard.

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

Q: Did you hear the operation sound?

YES : Go to Step 6.
NO : Refer to, DTC P0506

−

Idle Control System RPM

Lower Than Expected (

P.13A-265

), DTC P0507

−

Idle

Control System RPM Higher Than Expected(

P.13A-

274

).

STEP 6. Using scan tool MB991502, check actuator test
items 01, 02, 03, 04: Injector.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check following items in the actuator test. Refer to, Actuator

Test Reference Table(

P.13A-416

).

a. Item 01, 02, 03, 04: Injector.

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

Q: Is the actuator operating properly?

YES : Go to Step 7.
NO : Refer to, DTC P0201, P0202, P0203, P0204

−

Injector Circuit Malfunction(

P.13A-154

).

ACX02519 AH

IDLE AIR
CONTROL MOTOR

AC003081 AB

16 PIN

MB991502

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-338

STEP 7. Using scan tool MB991502, check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items in the data list. Refer to, Data List

Reference Table(

P.13A-405

).

a. Item 13: Intake Air Temperature Sensor.
b. Item 25: Barometric Pressure Sensor.

c. Item 21: Engine Coolant Temperature Sensor.

d. Item 59: Heated Oxygen Sensor (rear)
e. Item 11: Heated Oxygen Sensor (front)

f. Item 27: Power Steering Pressure Switch.

g. Item 28: A/C Switch

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

Q: Are they operating properly?

YES : Go to Step 8.
NO : Repair or replace. Then confirm that the malfunction

symptom is eliminated.

STEP 8. Using scan tool MB991502, check actuator test.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items in the actuator test. Refer to,

Actuator Test Reference Table(

P.13A-416

).

a. Item 08: Evaporative Emission Purge Solenoid.
b. Item 10: EGR Solenoid.

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

Q: Are they operating properly?

YES : Go to Step 9.
NO : Repair or replace. Then confirm that the malfunction

symptom is eliminated.

STEP 9. Using scan tool MB991502, check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items in the data list. Refer to, Data List

Reference Table(

P.13A-405

).

a. Item 45: Idle Air Control Motor Position.

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

Q: Is the actuator operating properly?

YES : Go to Step 10.
NO : Adjust the basic idle speed. Refer to, Basic Idle

Speed Adjustment(

P.13A-438

).

AC003081 AB

16 PIN

MB991502

AC003081 AB

16 PIN

MB991502

AC003081 AB

16 PIN

MB991502

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-339

STEP 10. Using scan tool MB991502, check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following items of the data list. Refer to, Data List

Reference Table(

P.13A-405

).

a. Item 11: Heated Oxygen Sensor (front)

•

Voltage should fluctuate between 0

−

0.4 volts and 0.6 -

1.0 volts while idling after the engine has been warmed.

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

Q: Is the sensor operating properly?

YES : Go to Step 12.
NO : Go to Step 11.

STEP 11. Check the fuel pressure.
Refer to, Fuel Pressure Test(

P.13A-439

).

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.

STEP 12. Check the ignition timing.
Refer to GROUP 11A, On-vehicle Service

−

Ignition Timing

Check (

P.11A-6

).

Q: Is the ignition timing 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 purge control system.

c. Check compression pressure.

d. Check if the foreign materials (water,

kerosene, etc.) got into fuel.

e. Check the EGR control system.

Then confirm that the malfunction symptom is

eliminated.

NO : Check that the crankshaft position sensor and timing

belt cover are in the correct position. Then confirm
that the malfunction symptom is eliminated.

AC003081 AB

16 PIN

MB991502

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-340

INSPECTION PROCEDURE 9: Idle speed is high (improper idle speed).

COMMENT

•

In such cases as the above, the cause is
probably that the intake air volume during idle is
too great.

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

•

Malfunction of the IAC system.

•

Malfunction of the throttle body.

DIAGNOSIS

Required Special Tool:
MB991502: Scan Tool (MUT-II)

STEP 1. Using scan tool MB991502, read the diagnostic
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 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 is output?

YES : Refer to, Diagnostic Trouble Code Chart(

P.13A-20

).

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: Disconnecting the engine coolant temperature
sensor connector and connecting the harness side of the
connector to another engine coolant temperature sensor
that is at 20

°

C (68

°

F) or below is also okay.

(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 be 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-265

), DTC P0507

−

Idle

Control System RPM Higher Than Expected (

P.13A-

274

).

AC003081 AB

16 PIN

MB991502

ACX02519 AH

IDLE AIR
CONTROL MOTOR