Mitsubishi Pajero Pinin. Manual - part 116

MPI <4G9> – 

Troubleshooting

13C-50

INSPECTION PROCEDURE 6

Initial combustion but no complete combustion
(starting impossible)

Probable cause

In such cases as the above, the cause is probably that the spark plugs are generating
sparks but the sparks are weak, or the initial mixture for starting is not appropriate.

D

Malfunction of the ignition system

D

Malfunction of the injector system

D

Foreign materials in fuel

D

Poor compression

D

Malfunction of the engine-ECU

OK

Check the following items.

D

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

D

Check if the injectors are clogged.

D

Check the compression pressure.

D

Check fuel lines for clogging.

D

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

NG

Check that the crank angle sensor is installed properly.

No

Check the ignition timing when cranking.

OK: Approx. 5

_

BTDC

OK

D

Clean the throttle valve area. (Refer to P.13C-96.)

NG

Check the ISC servo sys-
tem. (Refer to P.13C-40,
INSPECTION PROCE-
DURE FOR DIAGNOSIS
CODE P0505.)

Yes

Check ISC servo for op-
eration sound. 
(Refer to P.13C-107.)

OK

Is starting good if the engine is cranked with the accelerator pedal
slightly depressed?

OK

Can any sound be heard from the injectors when cranking?

NG

Check the injector system. (Refer to P.13C-30, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203, P0204.)

OK

MUT-

II

 Data list

18 Ignition switch-ST (Refer to P.13C-75.)

NG

Check the ignition switch-ST system.
(Refer to P.13C-71, INSPECTION PROCEDURE 28.)

OK

MUT-

II

 Data list

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

NG

Check the engine coolant temperature sensor system.
(Refer to P.13C-12, INSPECTION PROCEDURE FOR DIAGNO-
SIS CODE P0115.)

No

MUT-

II

 

Actuator test

07 Fuel pump (Refer to P.13C-79.)

NG

Check the fuel pump system.
(Refer to P.13C-69, INSPECTION PROCEDURE 27.)

OK

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

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

Check battery voltage when cranking.

OK: 8 V or higher

NG

Check the battery. (Refer to GROUP 54 – Battery.)

MPI <4G9> – 

Troubleshooting

13C-51

INSPECTION PROCEDURE 7

It takes too long time to start. (Incorrect starting)

Probable cause

In cases such as the above, the cause is probably that the spark is weak and
ignition is difficult, the initial mixture for starting is not appropriate, or sufficient
compression pressure is not being obtained.

D

Malfunction of the ignition system

D

Malfunction of the injector system

D

Inappropriate gasoline use

D

Poor compression

OK

Check the following items.

D

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

D

Check if the injectors are clogged.

D

Check the compression pressure.

D

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

OK

Check the ignition timing when cranking.

OK: Approx. 5

_

BTDC

NG

Check that the crank angle sensor is installed properly.

OK

Can any sound be heard from the injectors when cranking?

NG

Check the injector system. (Refer to P.13C-30, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,
P0204.)

OK

MUT-

II

 Data list

18 Ignition switch-ST (Refer to P.13C-75.)

NG

Check the ignition switch-ST system.
(Refer to P.13C-71, INSPECTION PROCEDURE 28.)

OK

MUT-

II

 Data list

21 Engine coolant temperature 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.)

Check the fuel pump system.
(Refer to P.13C-69, INSPECTION PROCEDURE 27.)

No

MUT-

II

 Actuator test

07 Fuel pump (Refer to P.13C-79.)

NG

OK

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

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

Check battery voltage when cranking

OK: 8 V or higher

NG

Check the battery. (Refer to GROUP 54 – Battery.)

MPI <4G9> – 

Troubleshooting

13C-52

INSPECTION PROCEDURE 8

Unstable idling (Rough idling, hunting)

Probable cause

In cases as the above, the cause is probably that the ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
Because the range of possible causes is broad, inspection is narrowed down to
simple items.

D

Malfunction of the ignition system

D

Malfunction of air-fuel ratio control system

D

Malfunction of the ISC system

D

Malfunction of the purge control solenoid valve system

D

Malfunction of the EGR solenoid valve system

D

Poor compression

D

Drawing air into exhaust system

To the next page

NG

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

OK

MUT-

II

 Actuator test

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

NG

Check the purge control solenoid valve system 
(Refer to P.13C-38, INSPECTION PROCEDURE FOR DIAGNO-
SIS CODE P0443.)

OK

MUT-

II

 Actuator test

08 Purge control solenoid valve (Refer to P.13C-79.)

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 the injector system. (Refer to P.13C-30, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203, P0204.)

OK

Check the injector for operation sound.

NG

Check the ISC system. (Refer to P.13C-40, INSPECTION PROCE-
DURE FOR DIAGNOSIS CODE P0505.)

No

Check the ISC servo for operation sound. (Refer to P.13C-107.)

NG

Inspect the intake of air into the air intake system

D

Broken intake manifold gasket

D

Broken air intake hose

D

Broken vacuum hose

D

Positive crankcase ventilation valve does not operate.

Check the trouble symptom.

No

Does idling speed fluctuate excessively?

Yes

Clean the throttle body. (Refer to P.13C-96.)

No

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

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

Were the battery terminals disconnected?

Yes

After warming-up, let the engine run at idling for 10 minutes.

OK

MPI <4G9> – 

Troubleshooting

13C-53

OK

Check the following items.

D

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

D

Check the purge control system.

D

Check the EGR control system.

D

Check the compression pressure.

D

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

NG

Check that the crank angle sensor is installed properly.

OK

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

NG

Adjust the basic idle speed. (Refer to P.13C-97.)

OK

MUT-

II

 Data list

45 ISC Servo position (Refer to P.13C-77.)

NG

Check the ignition switch-ST. 
(Refer to P.13C-71, INSPECTION PROCEDURE 28.)

OK

MUT-

II

 Data list

29 Inhibitor switch (Refer to P.13C-76.)

NG

Check the A/C switch and A/C relay system. 
(Refer to P.13C-72, INSPECTION PROCEDURE 29.)

OK

MUT-

II

 Data list

28 A/C switch (Refer to P.13C-76.)

NG

Check the power steering
fluid pressure switch sys-
tem.  (Refer to P.13C-43,
INSPECTION PROCE-
DURE FOR DIAGNOSIS
CODE P0551.)

OK

MUT-

II

 Data list

27 Power steering fluid pressure switch (Refer to P.13C-76.)

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: 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

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