Mitsubishi Colt Ralliart. Manual - part 732

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-253

STEP 8: Connector check: A-114 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Check and repair harness between A-125 

(terminal No. 1) starter connector and A-114 
(terminal No. 39) engine-ECU connector.

• Check output line for open circuit or 

damage.

NO : 

Repair or replace.

STEP 9. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item 22: Crank angle sensor

Q: Is the check result normal?

YES : 

Go to Step 10 .

NO : 

Check crank angle sensor system (Refer to 
Code No. P0335 

P.13B-142

).

STEP 10. Visual check of ignition spark.

• Remove the spark plug and install it to the ignition 

coil.

• Connect the ignition coil connector.

• Remove all injector connector.

• At the engine start, check each spark plug pro-

duces a spark.

Q: Is the check result normal?

YES : 

Go to Step 12 

NO : 

Go to Step 11 

STEP 11. Check spark plug.

• Check spark plug (Refer to GROUP 16 − Ignition 

System 

− On-vehicle Service 

P.16-35

).

Q: Is the check result normal?

YES : 

Check ignition circuit system (Refer to 

Inspection Procedure 26 

P.13B-327

).

NO : 

Replace spark plug.

STEP 12. Check injector for operating sound.

• While cranking the engine, check each injector 

for operating sound (Refer to 

P.13B-367

).

Q: Can operating sound be heard?

YES : 

Go to Step 13 

NO : 

Check the injector system of the defective 

cylinder.

(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

).

STEP 13. Fuel pressure measurement

• Fuel pressure measurement (Refer to Fuel Pres-

sure Test 

P.13B-358

).

Q: Is the check result normal?

YES : 

Go to Step 14 .

NO : 

Repair.

STEP 14. Replace engine-ECU

• After replacing the engine-ECU, re-check the 

trouble symptoms.

Q: Does trouble symptom recur?

YES : 

Check if there is foreign material (water, 

kerosene, etc.) in fuel. Replace as required.

NO : 

Check end.

AK402745

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L

AF

A-114

Connector: 

A-114

Harness side connector

Engine-ECU

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-254

Inspection Procedure 6: Starting Impossible (Initial Combustion But No Complete Combustion), 
Improper Starting (Long Time to Start)

COMMENT ON TROUBLE SYMPTOM

• Failure is possibly caused by poor ignition, incor-

rect air-fuel ratio at cranking, improper fuel pres-
sure or other faults.

PROBABLE CAUSES

• Failed battery

• Failed ignition system

• Failed fuel system

• Failed air-fuel ratio control system

• Failed intake system

• Failed exhaust emission control system

• Throttle valve body fouled

• Incorrectly installed timing belt

• Incorrect compression pressure

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery condition.

Q: Have the battery terminals been disconnected 

recently?
YES : 

Perform idle learning (Refer to GROUP 00 

− 

Precautions Before Service 

− Learning 

Procedure for Idling in MPI Engine 

P.00-21

).

NO : 

Go to Step 2 .

STEP 2. Check battery voltage.

• Perform battery voltage measurement during 

cranking.

OK: 8 V or higher

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Check battery (Refer to GROUP 54A 

− 

Battery 

− On-vehicle Service − Battery Test 

P.54A-5

).

STEP 3. M.U.T.-III diagnosis code

Q: Is the diagnosis code output?

YES : 

Inspection chart for diagnosis codes (Refer 

to 

P.13B-18

).

NO : 

Go to Step 4 .

STEP 4. 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: Are the check results normal?

YES : 

Go to Step 5 .

NO : 

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

P.13B-18

).

STEP 5. Check throttle body (throttle valve) for 
contamination.

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Clean throttle body (throttle valve) (Refer to 

P.13B-358

).

STEP 6. M.U.T.-III actuator test

• Item 07: Fuel pump relay

OK: There should be fuel pump operating 
sound.

Q: Is the check result normal?

YES : 

Go to Step 7 .

NO : 

Check fuel pump system (Refer to 
Inspection Procedure 22 

P.13B-290

). 

STEP 7. Check air intake from intake hose and 
intake manifold.

Q: Is the check result normal?

YES : 

Go to Step 8 .

NO : 

Repair.

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-255

STEP 8. Check injector for operating sound.

• While cranking the engine, check each injector 

for operating sound (Refer to 

P.13B-367

). 

Q: Is there injector operating sound?

YES : 

Go to Step 9 .

NO : 

Check the injector system of the effective 

cylinder.

 (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

). 

STEP 9. Check timing marks of the timing belt.

Q: Is the check result normal?

YES : 

Go to Step 10 .

NO : 

Align timing marks.

STEP 10. Visual check of ignition spark.

• Remove the spark plug and install it to the ignition 

coil.

• Connect the ignition coil connector.

• Remove all injector connector.

• At the engine start, check each spark plug pro-

duces a spark.

Q: Is the check result normal?

YES : 

Go to Step 12 

NO : 

Go to Step 11 

STEP 11. Check spark plug.

• Check spark plug (Refer to GROUP 16 − Ignition 

System 

− On-vehicle Service 

P.16-35

).

Q: Is the check result normal?

YES : 

Check ignition circuit system (Refer to 

Inspection Procedure 26 

P.13B-327

).

NO : 

Replace spark plug.

STEP 12. Check injector spray condition.

• Check every injector for correct spray condition 

(Refer to 

P.13B-367

).

Q: Is the check result normal?

YES : 

Go to Step 13 .

NO : 

Replace injector.

STEP 13. Fuel pressure measurement

• Perform fuel pressure measurement (Refer to 

Fuel Pressure Test 

P.13B-358

).

Q: Is the check result normal?

YES : 

Go to Step 14 .

NO : 

Repair.

STEP 14. Check compression pressure.

• Check compression pressure (Refer to GROUP 

11C 

− On-vehicle Service − Compression Pres-

sure Check 

P.11C-13

).

Q: Is the check result normal?

YES : 

Go to Step 15 .

NO : 

Repair.

STEP 15. Replace engine-ECU

• After replacing the engine-ECU, re-check the 

trouble symptoms.

Q: Does trouble symptom recur?

YES : 

Check if there is foreign material (water, 

kerosene, etc.) in fuel. Replace as required.

NO : 

Check end.

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-256

Inspection Procedure 7: Unstable Idling (Rough Idling, Hunting), Improper Idling Speed (Too High or 
too Low), Engine Stalls during Idling (Die Out)

COMMENT ON TROUBLE SYMPTOM

• Probable causes range widely from ignition sys-

tem, air-fuel ratio, and electronically controlled 
throttle valve, to fuel system. A sudden engine 
stall is possibly caused by poor connector con-
tact.

PROBABLE CAUSES

• Failed ignition system

• Failed fuel system

• Failed air-fuel ratio control system

• Failed intake/exhaust system

• Failed exhaust emission control system

• Throttle valve body fouled

• Incorrectly installed timing belt

• Incorrect compression pressure

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery condition.

Q: Have the battery terminals been disconnected 

recently?
YES : 

Perform idle learning (Refer to GROUP 00 

− 

Precautions Before Service Learning 
Procedure for Idling in MPI Engine 

P.00-21

).

NO : 

Go to Step 2 .

STEP 2. M.U.T.-III diagnosis code

Q: Is the diagnosis code output?

YES : 

Inspection chart for diagnosis codes (Refer 

to 

P.13B-18

).

NO : 

Go to Step 3 .

STEP 3. 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 14: Throttle position sensor (sub)

d. Item 21: Engine coolant temperature sensor
e. Item 25: Barometric pressure sensor

f. Item 77: Accelerator pedal position sensor 

(sub)

g. Item 78: Accelerator pedal position sensor 

(main)

h. Item 79: Throttle position sensor (main)

Q: Are the check results normal?

YES : 

Go to Step 4 .

NO : 

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

P.13B-18

).

STEP 4. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item 67: Stop lamp switch

Q: Are the check results normal?

YES : 

Go to Step 5 .

NO : 

Perform the diagnosis code classified check 
procedure for the switch that has shown an 
abnormal data value (Refer to 

P.13B-20

).

STEP 5. Check air intake from intake hose and 
intake manifold.

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Repair.

STEP 6. Check timing marks of the timing belt.

Q: Is the check result normal?

YES : 

Go to Step 7 .

NO : 

Align timing marks.

STEP 7. Check throttle body (throttle valve) for 
contamination.

Q: Is the check result normal?

YES : 

Go to Step 8 .

NO : 

Clean throttle body (throttle valve) (Refer to 

P.13B-358

).

STEP 8. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item 11: oxygen sensor (front)
b. Item 59: oxygen sensor (rear)

Q: Is the check results normal?

YES : 

Go to Step 9 .

NO : 

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

P.13B-18

).

Main

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TOC