Mitsubishi Pajero Pinin. Manual - part 119

MPI <4G9> – 

Troubleshooting

13C-62

OK

Check the following items.

D

Check the ignition coil, spark plugs, spark plug cables.

D

Check the compression pressure.

D

Check the fuel filter or fuel line for clogging.

D

Broken air intake hose

D

Clogged air cleaner

OK

Check the fuel pressure. (Refer to P.13C-98.)

OK

1. Inspect the intake of

air into the air intake
system

D

Broken intake 
manifold gasket

D

Broken vacuum 
hose

D

PCV valve does
not operate.

D

Broken air intake
hose

2. Check the injector for

clog.

NG

Check the fuel pressure.
(Refer to P.13C-98.)

OK

MUT-

II

 Data list

11 Oxygen sensor

OK: Changes between 0 – 400 mV and 600 – 1,000 mV

during idling

From the previous page

MPI <4G9> – 

Troubleshooting

13C-63

INSPECTION PROCEDURE 19

Surge

Probable cause

Defective ignition system, abnormal air-fuel ratio, etc. are suspected.

D

Malfunction of the ignition system

D

Malfunction of air-fuel ratio control system

D

Malfunction of the EGR control solenoid valve system

OK

Check the following items.

D

Check the ignition coil, spark plugs, spark plug cables.

D

Check the EGR control system.

OK

Check the fuel pressure. (Refer to P.13C-98.)

OK

1. Inspect the intake of

air into the air intake
system

D

Broken intake 
manifold gasket

D

Broken vacuum 
hose

D

PCV valve does
not operate.

D

Broken air intake
hose

2. Check the injector for

clog.

NG

Check the fuel pressure.
(Refer to P.13C-98.)

OK

MUT-

II

 Data list

11 Oxygen sensor

OK: Changes between 0 – 400 mV and 600 – 1,000 mV

during idling

NG

Check the oxygen sensor (front) system. (Refer to P.13C-25, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)

OK

MUT-

II

 Data list

11 Oxygen sensor

OK: Changes between 600 – 1,000 mV during sudden racing

NG

Check the oxygen sensor (rear) system. (Refer to P.13C-27, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)

OK

MUT-

II

 Data list

59 Oxygen sensor (rear)

D

Transmission: 2nd gear <M/T>, L range <A/T>

D

Driving with throttle widely open
OK: 600 – 1,000 mV

NG

Check the EGR control solenoid valve system. 
(Refer to P.13C-36, INSPECTION PROCEDURE FOR DIAGNO-
SIS CODE P0403.)

OK

MUT-

II

 Actuator test

10 EGR control solenoid valve (Refer to P.13C-79.)

NG

Check the throttle position sensor system. (Refer to P.13C-22,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0120.)

OK

MUT-

II

 Data list

14 Throttle position sensor (Refer to P.13C-75.)

NG

Check the engine coolant temperature sensor system. 
(Refer to P.13C-20, INSPECTION PROCEDURE FOR DIAGNO-
SIS CODE P0115.)

OK

MUT-

II

 Data list

21 Engine coolant temperature sensor (Refer to P.13C-75.)

NG

Check the barometric pressure sensor system. (Refer to P.13C-16.
INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)

OK

MUT-

II

 Data list

25 Barometric pressure sensor (Refer to P.13C-76.)

NG

Check the intake air temperature sensor system. (Refer to
P.13C-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE
P0110.)

OK

MUT-

II

 Data list

13 Intake air temperature sensor (Refer to P.13C-74.)

NG

Check that the crank angle sensor is installed properly.

OK

Check the ignition timing. 
(Refer to GROUP 11C – On-vehicle Service.)

NG

Check the injector system. (Refer to P.13C-32, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203, P0204.)

No

Check the injectors for operation sound.

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

Refer to P.13C-12, INSPECTION CHART FOR DIAGNOSIS
CODES.

MPI <4G9> – 

Troubleshooting

13C-64

INSPECTION PROCEDURE 20

Knocking

Probable cause

In cases as the above, the cause is probably that the detonation control is defective
or the heat value of the spark plug is inappropriate.

D

Defective detonation sensor

D

Inappropriate heat value of the spark plug

Yes

Check the following items.

D

Spark plugs

D

Check if foreign materials (water, alcohol, etc.) got into fuel.

No

Check the detonation sensor system. (Refer to P.13C-33, INSPEC-
TION PROCEDURE FOR DIAGNOSIS CODE P0325.)

No

Does knocking occur when driving with the sensor disconnected?
At this time, use the MUT-

II

 to check if the timing is retarded

compared to when the detonation sensor connector is connected.

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

Refer to P.13C-12, INSPECTION CHART FOR DIAGNOSIS
CODES.

INSPECTION PROCEDURE 21

Dieseling

Probable cause

Fuel leakage from injectors is suspected.

D

Fuel leakage from injectors

Check the injectors for fuel leakage.

MPI <4G9> – 

Troubleshooting

13C-65

INSPECTION PROCEDURE 22

Too high CO and HC concentration when idling

Probable cause

Abnormal air-fuel ratio is suspected.

D

Malfunction of the air-fuel ratio control system

D

Deteriorated catalyst

NG

Replace the catalytic converter.

Check the trouble symptom.

OK

NG

Check the following items.

D

Check the injectors for operation sound.

D

Check the injectors for fuel leakage.

D

Check the ignition coil, spark plugs, spark plug cables.

D

Check the compression pressure.

D

Check the positive crankcase ventilation system.

D

Check the purge control system.

D

Check the EGR control system.

NG

Check the fuel pressure. (Refer to P.13C-98.)

Check the trouble symptom.

OK

Replace the oxygen sensor.

OK

MUT-

II

 Data list

11 Oxygen sensor

OK: Repeat 0 – 400 mV and 600 – 1,000 mV alternately

when idling.

NG

Check the oxygen sensor (front) system. (Refer to P.13C-25, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)

OK

MUT-

II

 Data list

11 Oxygen sensor

OK: 600  – 1,000 mV when racing suddenly.

NG

Check the oxygen sensor (rear) system. (Refer to P.13C-27, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)

OK

MUT-

II

 Data list

59 Oxygen sensor (rear)

D

Transmission: 2nd gear <M/T>, L range <A/T>

D

Driving with throttle widely open
OK: 600 – 1,000 mV

NG

Check the barometric pressure sensor system. (Refer to P.13C-16,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)

OK

MUT-

II

 Data list

25 Barometric pressure sensor (Refer to P.13C-76.)

NG

Check the intake air temperature sensor system. (Refer to
P.13C-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE
P0110.)

OK

MUT-

II

 Data list

13 Intake air temperature sensor (Refer to P.13C-74.)

NG

Check the engine coolant temperature sensor system. 
(Refer to P.13C-20, INSPECTION PROCEDURE FOR DIAGNO-
SIS CODE P0115.)

OK

MUT-

II

 Data list

21 Engine coolant temperature sensor. (Refer to P.13C-75.)

NG

Check that the crank angle sensor is installed properly.

No

Check the ignition timing. 
(Refer to GROUP 11B – On-vehicle Service.)

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

Refer to P.13C-12, INSPECTION CHART FOR DIAGNOSIS
CODES.