Mitsubishi Galant 9G. Manual — part 1185

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1040

STEP 10. Check harness connector B-03 or B-04 or B-01 at
right bank injector for damage.
(1) Check the injector connector, which deviated from the

standard value listed in Step 8.

Q: Is the harness connector in good condition?

YES : Repair harness wire between injector intermediate

connector and right bank injector connector because
of harness damage. Then confirm that the
malfunction symptom is eliminated.

NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then confirm that the

malfunction symptom is eliminated.

STEP 11. Check harness connector B-32 at the
intermediate connector for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 12.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then confirm that the

malfunction symptom is eliminated.

STEP 12. Check harness connector B-27, B-26, B-30 at the
left bank injector for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 13.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then confirm that the

malfunction symptom is eliminated.

AK303055

M

1

2

CONNECTOR: B-01, B-03, B-04

AB

B-01 (GR)

B-03 (GR)

B-04 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AK303053

3

4

5

8

9

1

2

6

7

10

CONNECTOR: B-32

HARNESS CONNECTOR:
COMPONENT SIDE

AB

B-32 (B)

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

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1041

STEP 13. Check the harness connector B-23 at the PCM for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 14.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then confirm that the

malfunction symptom is eliminated.

127 126 125 124 123 122 121

133 132 131 130 129 128

140 139 138 137 136 135 134

146 145 144 143 142 141

153 152 151 150 149 148 147

AK303058

HARNESS CONNECTOR:
COMPONENT SIDE

CONNECTOR: B-23

B-23

PCM

AB

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1042

STEP 14. Check for harness damage between injector
connector and PCM connector.

a. Check the harness wire between injector connector

B-01 (terminal No. 2) and PCM connector B-23 (terminal
No. 153) at No. 1 cylinder injector.

b. Check the harness wire between injector connector

B-30 (terminal No. 2) and PCM connector B-23 (terminal
No. 146) at No. 2 cylinder injector.

c. Check the harness wire between injector connector

B-03 (terminal No. 2) and PCM connector B-23 (terminal
No. 140) at No. 3 cylinder injector.

d. Check the harness wire between injector connector

B-27 (terminal No. 2) and PCM connector B-23 (terminal
No. 139) at No. 4 cylinder injector.

e. Check the harness wire between injector connector

B-04 (terminal No. 2) and PCM connector B-23 (terminal
No. 133) at No. 5 cylinder injector.

f. Check the harness wire between injector connector

B-26 (terminal No. 2) and PCM connector B-23 (terminal
No. 127) at No. 6 cylinder injector.

Q: Is the harness wire in good condition?

YES : Check the following items, and repair or replace the

defective items.

a. Check the ignition coil and spark plugs.
b. Check if the injectors are clogged.
c. Check the compression pressure.
d. Check if the foreign materials (water,

kerosene, etc.) got into fuel.

Then confirm that the malfunction symptom is

eliminated.

NO : Repair it. Then confirm that the malfunction symptom

is eliminated.

INSPECTION PROCEDURE 8: Unstable Idle (Rough Idle, Hunting).

.

COMMENT

• In cases such as the above, the cause is proba-

bly the air/fuel mixture or electronic control throt-
tle valve system. Other systems affecting idle
quality include the ignition system and compres-
sion.

.

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

• Malfunction of the ignition system.

• Malfunction of air/fuel ratio control system.

• Malfunction of the electronic control throttle valve

system.

• Malfunction of the evaporative emission purge

solenoid system.

• Malfunction of the EGR valve.

• Poor compression pressure.

• Vacuum leak.

AK303235

M

1

2

AB

B-30 (GR)

B-04 (GR)

B-01 (GR)

B-27 (GR)

B-03 (GR)

B-26 (GR)

CONNECTOR: B-01, B-03, B-04, B-26,B-27,
B-30

HARNESS CONNECTOR:
COMPONENT SIDE

127 126 125 124 123 122 121

133 132 131 130 129 128

140 139 138 137 136 135 134

146 145 144 143 142 141

153 152 151 150 149 148 147

AK303058

HARNESS CONNECTOR:
COMPONENT SIDE

CONNECTOR: B-23

B-23

PCM

AB

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1043

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Check if the battery terminal is disconnected
Q: Has the battery terminal been disconnected lately?

YES : Start the engine and let it run at idle for approximate

10 minutes after engine warm up. Then, if a
malfunction occurs, go to Step 2.

NO : Go to Step 2.

STEP 2. Using scan tool MB991958, read the diagnostic
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch is 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 the DTC set?

YES : Refer to Diagnostic Trouble Code Chart

P.13B-34

.

NO : Go to Step 3.

STEP 3. Check the engine idling state.
Q: Is it noticeably hunting?

YES : Go to Step 4.
NO : Go to Step 5.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827