Mitsubishi Colt Ralliart. Manual — part 691

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-89

STEP 9. Check harness between B-53 (terminal
No. 4) oxygen sensor (rear) connector and B-106
(terminal No. 4) engine control relay connector.

NOTE: Before checking harness, check intermediate
connector B-112, and repair if necessary.

• Check power supply line for damage.

Q: Is the check result normal?

YES :

Go to Step 10 .

NO :

Repair the damaged harness wire.

STEP 10. Check harness between B-53 (terminal
No. 3) oxygen sensor (rear) connector and A-08
(terminal No. 79) engine-ECU connector.

• Check earthing line for damage.

Q: Is the check result normal?

YES :

Go to Step 11 .

NO :

Repair the damaged harness wire.

AK402019

3

2

1

4

Oxygen sensor (rear)

Connector: B-53

B-53 Harness side connector

AC

B-53

3

2

1

4

AK402084

J/B side
connector

B-106

Connector: B-106
J/B (front side)

AC

AK402019

3

2

1

4

Oxygen sensor (rear)

Connector: B-53

B-53 Harness side connector

AC

B-53

AK402725

77

78

79

80

81

82

83

84

92

93

94

95

96

97

98

99

85

86

87

88

89

90

91

100

101

102

103

104

105

106

115

116

117

118

119

120

121

107

108

109

110

111

112

113

114

130

131

132

133

134

135

136

122

123

124

125

126

127

128

129

72 71

74 73

76 75

R

AI

A-08

Connector:

A-08

A-08 Special tool power plant ECU check
harness

Engine-ECU

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-90

STEP 11. M.U.T.-III diagnosis code.

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

YES :

Replace engine-ECU.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions

P.00-13

).

Code No. P0170: Abnormal Fuel System

OPERATION

• Refer to Code No. P0201: No. 1 Injector System

P.13B-92

.

• Refer to Code No. P0202: No. 2 Injector System

P.13B-97

.

• Refer to Code No. P0203: No. 3 Injector System

P.13B-102

.

• Refer to Code No. P0204: No. 4 Injector System

P.13B-107

.

FUNCTION

• If the fuel system goes out of order, the fuel cor-

rection value will become larger.

• The engine-ECU checks whether the fuel correc-

tion value is within a specified range.

TROUBLE JUDGEMENT

Check Condition

• In learning air-fuel ratio

Judgement Criterion

• For more than 5 seconds, compensation value in

fuel injection amount is too low.

Or

• For more than 5 seconds, compensation value in

fuel injection amount is too high.

PROBABLE CAUSES

• Failed fuel supply system

• Failed oxygen sensor

• Failed intake air temperature sensor

• Failed engine coolant temperature sensor

• Failed air flow sensor

• Failed barometric pressure sensor

• Air drawn in from intake hose and inlet manifold

• Exhaust leak from exhaust manifold

• Failed throttle body (throttle valve area) fouled

• Failed injector

• Failed purge control solenoid valve

• Fuel pressure improper

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Is any other diagnosis code than P0170 output?

YES :

Refer to Inspection Chart for Diagnosis

Code

P.13B-18

.

NO :

Go to Step 2.

STEP 2. M.U.T.-III data list

• Refer to Data List Reference Table

P.13B-335

.

a. Item 12: Air flow sensor
b. Item 13: Intake air temperature sensor

c. Item 21: Engine coolant temperature sensor

d. Item 25: Barometric pressure sensor

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Perform the diagnosis code classified check
procedure on the sensor that has shown an
abnormal data value (Refer to Inspection
Chart for Diagnosis Code

P.13B-18

).

STEP 3. Check for ingress of air from intake hose
and inlet manifold.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair.

STEP 4. Check for leakage of exhaust emission
from exhaust manifold.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair.

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-91

STEP 5. Check throttle body (throttle valve
portion) for foul.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Clean throttle body (throttle valve portion)
(Refer to

P.13B-358

).

STEP 6. M.U.T.-III data list

• Refer to Data List Reference Table

P.13B-335

.

a. Item 11: Oxygen sensor (front)

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Check oxygen sensor system (Refer to
Code No. P0130

P.13B-65

).

STEP 7. Check injector itself.

• Check injector itself (Refer to

P.13B-367

).

Q: Is the check result normal?

YES :

Go to Step 8.

NO :

Replace injector.

STEP 8. Check purge control solenoid valve
itself.

• Check purge control solenoid valve itself (Refer

to GROUP 17

− Emission Control System −

Evaporative Emission Control System

− Purge

Control Solenoid Valve

P.17-16

).

Q: Is the check result normal?

YES :

Go to Step 9.

NO :

Replace purge control solenoid valve.

STEP 9. Fuel pressure measurement

• Fuel pressure measurement (Refer to

P.13B-358

).

Q: Is the check result normal?

YES :

Replace engine-ECU.

NO :

Repair.

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-92

Code No. P0201: No. 1 injector System

OPERATION

• Power is supplied to the injector (terminal No. 1)

through the engine control relay (terminal No. 4).

• The engine-ECU (terminal No. 8) turns on the

power transistor in the unit to activate the injector
(terminal No. 2).

AK402684

2

1

3

1

2

4

19

21

20

18

17

16

15

14

1213

11

8 9

L

10

37
52 53 54 555657585960616263646566

38 39 404142434445464748495051

22 23 24 252627282930313233343536

7

5

3

1

6

4

2

A-114

AN

B-106

A-17

B-112

B-108

Engine
control
relay

Injector
No. 1

A-102

(MU802062)

4

6

4

1

2

2

8

No. 1 Injector Circuit

R

R

Wire colour code
B: Black LG: Light green G: Green L: Blue W: White Y: Yellow SB: Sky blue BR: Brown O: Orange GR: Gray
R: Red P: Pink V: Violet P: Purple

Y-V

3

1

1

1

R

Fusible link

16

20A

J/B

To engine-ECU

Engine-ECU

Main

Index

Group

TOC