Mitsubishi Galant 9G. Manual — part 1182

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1028

STEP 15. 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 if fuel is contaminated.
d. Check compression.

Then confirm that the malfunction symptom is

eliminated.

NO : Repair it. Then confirm that the malfunction symptom

is eliminated.

INSPECTION PROCEDURE 6: Starts Up and Dies.

.

COMMENT

• In such cases as the above, the cause is usually

improper air/fuel mixture. It is possible, though
less likely, that the spark plugs are generating
sparks but the sparks are weak.

.

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

• Malfunction of the ignition system.

• Malfunction of the injector system.

• Contaminated fuel.

• Poor compression.

• Dirtiness around throttle valve.

• Malfunction of the PCM.

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

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MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1029

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Measure the battery positive voltage.
(1) Measure the battery positive voltage during cranking.

• The voltage should be 8 volts or more.

Q: Does the voltage remain greater than 8 volts while the

engine is cranked?
YES : Go to Step 2.
NO : Refer to GROUP 54A, Battery

− Battery Check

P.54A-5

.

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 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.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1030

STEP 3. Using scan tool MB991958, 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.13B-1152

.

a. Item 07: Fuel Pump.

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

YES : Go to Step 4.
NO : Repair or replace it. Then confirm that the malfunction

symptom is eliminated.

STEP 4. Using scan tool MB991958, 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.13B-1137

.

a. Item 21: Engine Coolant Temperature Sensor.

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

YES : Go to Step 5.
NO : Repair or replace it. Then confirm that the malfunction

symptom is eliminated.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1031

STEP 5. Inspection of throttle body (throttle valve area) for
dirtiness.
Q: Is the throttle valve area dirty?

YES : Refer to On-vehicle Service

− Throttle Body (Throttle

Valve Area) Cleaning.

P.13B-1178

.

NO : Go to Step 6.

STEP 6. Check the ignition timing.
(1) Check the ignition timing at cranking.

Standard value: 5

° BTDC ± 3°

Q: Is the ignition timing normal?

YES : Go to Step 7.
NO : Check that the crankshaft position sensor and timing

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

STEP 7. Check the left bank injector.
(1) Disconnect the left bank injector connector B-27, B-26,

B-30.

(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 8.
NO : Replace the faulty injector. Then confirm that the

malfunction symptom is eliminated.

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