Mitsubishi Pajero Pinin. Manual - part 117

MPI <4G9> – 

Troubleshooting

MPI <4G9> – 

Troubleshooting

13C-54

INSPECTION PROCEDURE 9

Idling speed is high. (Improper idling speed)

Probable cause

In such cases as the above, the cause is probably that the intake air volume during
idling is too great.

D

Malfunction of the ISC servo system

D

Malfunction of the throttle body

NG

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

Check the trouble symptom.

OK

Basic idle adjustment (Refer to P.13C-97.)

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 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 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.)

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

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

INSPECTION PROCEDURE 10

Idling speed is low. (Improper idling speed)

Probable cause

In cases such as the above, the cause is probably that the intake air volume during
idling is too small.

D

Malfunction of the ISC servo system

D

Malfunction of the throttle body

NG

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

Check the trouble symptom.

OK

Basic idle adjustment (Refer to P.13C-97.)

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.)

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.)

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.)

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Yes

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

MPI <4G9> – 

Troubleshooting

13C-55

INSPECTION PROCEDURE 11

When the engine is cold, it stalls at idling. (Die out)

Probable cause

In such cases as the above, the cause is probably that the air/fuel mixture is
inappropriate when the engine is cold, or that the intake air volume is insufficient.

D

Malfunction of the ISC servo system

D

Malfunction of the throttle body

D

Malfunction of the injector system

D

Malfunction of the ignition system

OK

Check the following items.

D

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

D

Check the compression pressure.

D

Check the engine oil viscosity.

NG

Check that the crank angle sensor is installed properly.

OK

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

OK

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

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 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 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.)

Yes

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

No

Check if the unstable idling (Rough idling, hunting). 
(Refer to P.13C-52, INSPECTION PROCEDURE 8.)

No

Is engine-idling stable after the warming-up?

Yes

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

No

Does the engine stall right after the accelerator pedal is released?

Yes

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

No

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Were the battery terminals disconnected?

Yes

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

MPI <4G9> – 

Troubleshooting

13C-56

INSPECTION PROCEDURE 12

When the engine is hot, it stalls at idling. (Die out)

Probable cause

In such cases as the above, the cause is probably that ignition system, air/fuel
mixture, idle speed control (ISC) or compression pressure is defective.
In addition, if the engine suddenly stalls, the cause may also be a defective connector
contact.

D

Malfunction of the ignition system

D

Malfunction of air-fuel ratio control system

D

Malfunction of the ISC system

D

Drawing air into intake system

D

Improper connector contact

To the next page

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 DIAGNOSIS CODE P0403.)

OK

MUT-

II

 Actuator test

10 EGR 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-15,
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.)

No

While carrying out an intermittent malfunction simulation test (Refer
to GROUP 00 – Points to Note for Intermittent Malfunctions.),
check for sudden changes in the signals shown below.

D

Crank angle sensor signal

D

Air flow sensor signal

D

Injector drive signal

D

Primary and secondary
ignition signal

D

Fuel pump drive signal

D

Engine-ECU power 
supply voltage

No

Does the engine stall easily again?

Yes

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

OK

Does the engine stall right after the accelerator pedal is released?

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.)

Yes

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

No

MUT-

II

 Self-Diag code

Are diagnosis codes displayed?

Were the battery terminals disconnected?

Yes

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

OK

MPI <4G9> – 

Troubleshooting

13C-57

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.

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-107.)

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

From the previous page