Mitsubishi Grandis. Manual - part 723

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-143

STEP 7. Check for intake of air from intake hose 
and inlet manifold.

Q: Is the check result normal?

YES : 

 Go to Step 8 .

NO : 

Repair.

STEP 8. Check for skipped timing belt teeth.

Q: Is the check result normal?

YES : 

 Go to Step 9 .

NO : 

Repair.

STEP 9. Check EGR valve (stepper motor) itself.

• Check EGR valve (stepper motor) itself [Refer to 

GROUP 17 

− Exhaust Gas Recirculation (EGR) 

System 

− EGR Valve (Stepper Motor) Check 

P.17-65

 ].

Q: Is the check result normal?

YES : 

 Go to Step 10.

NO : 

Replace EGR valve (stepper motor)

STEP 10. Check the trouble symptoms.

Q: Does trouble symptom persist?

YES : 

Replace engine-ECU <M/T> or 

engine-A/T-ECU <A/T>.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service 
Points

P.00-5

).

Code No. P0301: No. 1 Cylinder Misfire Detected

OPERATION

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

P.13A-115

.

FUNCTION

• If a misfire occurs while the engine is running, the 

engine speed changes for an instant.

• The engine-ECU <M/T> or engine-A/T-ECU 

<A/T> checks for such changes in engine speed.

TROUBLE JUDGMENT

Check Conditions

• Engine speed is 500 − 6,500 r/min.

• Engine coolant temperature is −10°C or higher.

• Barometric pressure is 76 kPa or higher.

• Volumetric efficiency is between 30% and 55 %.

• Adaptive learning is complete for the vane which 

generates a crankshaft position signal.

• While the engine is running, excluding gear 

shifting, deceleration, sudden 
acceleration/deceleration and A/C compressor 
switching.

• The throttle deviation is −0.06 V/10 ms to +0.06 

V/10 ms.

Judgment Criteria (change in the angular 

acceleration of the crankshaft is used for 
misfire detection).

• Misfire has occurred more frequently than the 

limit during the last 200 revolutions (when the 
catalyst temperature has been 950

°C or higher).

or

• Misfire has occurred 15 times or more in the last 

1,000 revolutions (that has been equivalent to 
approximately 1.5 times the emission standard).

PROBABLE CAUSE

• Ignition system related part(s) failed

• Low compression pressure

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1.Check ignition coil spark. 

Q: Is the check result normal?

YES : 

Go to Step 2 .

NO : 

Check ignition circuit system (Refer to 
Inspection procedure 26 

P.13A-355

)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-144

STEP 2.Connector check: B-101 No. 1 injector 
connector

Q: Is the check result normal?

YES : 

 Go to Step 3 .

NO : 

Repair or replace.

STEP 3.Check No. 1 injector itself.

• Check Injector itself (Refer to 

P.13A-393

).

Q: Is the check result normal?

YES : 

 Go to Step 4 .

NO : 

Replace No. 1 injector.

STEP 4.Connector check: B-15X engine control 
relay connector and C-110 engine-ECU <M/T> 
connector or engine-A/T-ECU <A/T> connector

Q: Is the check result normal?

YES : 

Go to Step 5 .

NO : 

Repair or replace.

AK300978

M

1

2

AJ

B-101 (GR)

Harness side connector

Connector: B-101

AK300967

2

1

3

4

AC

Harness side
connector

B-15X

Connector: B-15X

Relay box’s
triangle marks

AK305618AB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

Connector: C-110

<L.H. drive vehicles>

<R.H. drive vehicles>

C-110 (GR)

C-110 (GR)

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-145

STEP 5.Check harness between B-15X (terminal 
No. 1) engine control relay connector and B-101 
(terminal No. 1) No. 1 injector connector. 

NOTE: Before checking harness, check intermediate 
connector C-116, and repair if necessary.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

 Go to Step 6 .

NO : 

Repair.

STEP 6. Check harness between B-101(terminal 
No. 2) No. 1 injector connector and C-110 
(terminal No. 1) engine-ECU <M/T> connector or 
engine-A/T-ECU <A/T> connector

• Check output line for damage.

Q: Is the check result normal?

YES : 

 Go to Step 7 .

NO : 

Repair.

STEP 7. Fuel pressure measurement.

• Fuel pressure measurement (Refer to Fuel 

Pressure Test 

P.13A-383

).

Q: Is the check result normal?

YES : 

Go to Step 8 

NO : 

Repair.

STEP 8. Check the trouble symptoms.

Q: Does trouble symptom persist?

AK300967

2

1

3

4

AC

Harness side
connector

B-15X

Connector: B-15X

Relay box’s
triangle marks

AK300978

M

1

2

AJ

B-101 (GR)

Harness side connector

Connector: B-101

AK300978

M

1

2

AJ

B-101 (GR)

Harness side connector

Connector: B-101

AK305618AB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

Connector: C-110

<L.H. drive vehicles>

<R.H. drive vehicles>

C-110 (GR)

C-110 (GR)

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-146

YES : 

Replace engine-ECU <M/T> or 

engine-A/T-ECU <A/T>.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

P.00-5

).

Code No. P0302: No. 2 Cylinder Misfire Detected

OPERATION

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

P.13A-120

.

FUNCTION

• If a misfire occurs while the engine is running, the 

engine speed changes for an instant.

• The engine-ECU <M/T> or engine-A/T-ECU 

<A/T> checks for such changes in engine speed.

TROUBLE JUDGMENT

Check Conditions

• Engine speed is 500 − 6,500 r/min.

• Engine coolant temperature is −10°C or higher.

• Barometric pressure is 76 kPa or higher.

• Volumetric efficiency is between 30% and 55 %.

• Adaptive learning is complete for the vane which 

generates a crankshaft position signal.

• While the engine is running, excluding gear 

shifting, deceleration, sudden 
acceleration/deceleration and A/C compressor 
switching.

• The throttle deviation is −0.06 V/10 ms to +0.06 

V/10 ms.

Judgment Criteria (change in the angular 

acceleration of the crankshaft is used for 
misfire detection).

• Misfire has occurred more frequently than the 

limit during the last 200 revolutions (when the 
catalyst temperature has been 950

°C or higher).

Or

• Misfire has occurred 15 times or more in the last 

1,000 revolutions (that has been equivalent to 
approximately 1.5 times the emission standard).

PROBABLE CAUSE

• Ignition system related part(s) failed

• Low compression pressure

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1. Check ignition coil spark. 

Q: Is the check result normal?

YES : 

Go to Step 2 .

NO : 

Check ignition circuit system (Refer to 
Inspection Procedure 26 

P.13A-355

).

STEP 2. Check connector: B-102 No. 2 injector 
connector

Q: Is the check result normal?

YES : 

 Go to Step 3 .

NO : 

Repair or replace.

STEP 3. Check No. 2 injector itself.

• Check Injector itself (Refer to 

P.13A-393

).

Q: Is the check result normal?

YES : 

 Go to Step 4 .

NO : 

Replace No. 2 injector.

AK300978

M

1

2

AK

B-102 (GR)

Harness side connector

Connector: B-102