Mitsubishi Montero (2002-2004). Manual - part 835

ENGINE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-3

.

ENGINE CONTROL

GENERAL DESCRIPTION

M1171000100211

The accelerator cable has been discontinued, 
because the electronic-controlled throttle actuator 
control system has been adopted.

SPECIAL TOOL

M1171000600023

ENGINE CONTROL SYSTEM DIAGNOSIS

INTRODUCTION TO ENGINE CONTROL SYSTEM DIAGNOSIS

M1171002000209

If there is a malfunction in the engine control system, 
the accelerator pedal or throttle body may be faulty.

ENGINE CONTROL SYSTEM DIAGNOSTIC TROUBLESHOOTING STRATEGY

M1171002100228

Use these steps to plan your diagnostic strategy.
If you follow them carefully, you will be sure that you 
have exhausted most of the possible ways to find an 
engine control system fault.
1. Gather information from the customer.

2. Verify that the condition described by the 

customer exists.

3. Find the malfunction by following the Symptom 

Chart.

4. Verify that the malfunction is eliminated.

SYMPTOM CHART

M1171002200236

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Throttle Valve Will Not Fully Open or Close

DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

STEP 1. Check the accelerator pedal arm return spring.
Q: Is the accelerator pedal arm return spring damaged or 

deformed?
YES : Go to Step 2.
NO :  Replace, then go to Step 4.

TOOL

TOOL NUMBER AND 
NAME

SUPERSESSION

APPLICATION

MB991502 Scan tool 
(MUT-II)

MB991496-OD

Checking diagnostic 
trouble codes

B991502

SYMPTOM

INSPECTION PROCEDURE

REFERENCE PAGE

Throttle valve will not fully open or close

1

P.17-3

Accelerator pedal operation not smooth 
(over acceleration)

2

P.17-4

ENGINE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-4

STEP 2. Clean the throttle body. (Refer to GROUP 13A, On-
vehicle Service 

− Throttle Body Cleaning 

P.13Aa-11

.)

Q: Does the throttle valve fully open and close?

YES : The procedure is complete.
NO :  Go to Step 3.

STEP 3. Using scan tool MB991502, read the diagnostic 
trouble code.

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check for MFI system diagnostic trouble code.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is any DTC set?

YES : Refer to GROUP 13A, Diagnosis 

− Diagnostic 

Trouble Code Chart 

P.13Ab-22

.

NO :  Go to Step 4.

STEP 4. Retest the system.
Q: Does the throttle valve fully open and close?

YES : The procedure is complete.
NO :  Return to Step 1.

INSPECTION PROCEDURE 2: Accelerator Pedal Operation Not Smooth (Over Acceleration)

DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

STEP 1. Check the accelerator pedal.
Q: Is the accelerator pedal loose? 

YES : Tighten, then go to Step 4.
NO :  Go to Step 2.

STEP 2. Clean the throttle body. (Refer to GROUP 13A, On-
vehicle Service 

− Throttle Body Cleaning 

P.13Aa-11

.)

Q: Does the accelerator pedal work normally?

YES : The procedure is complete.
NO :  Go to Step 3.

ACX02258AC

MB991502

16-PIN

ENGINE CONTROL

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ENGINE AND EMISSION CONTROL

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STEP 3. Using scan tool MB991502, read the diagnostic 
trouble code.

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check for MFI system diagnostic trouble code.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is any DTC set?

YES : Refer to GROUP 13A, Diagnosis 

− Diagnostic 

Trouble Code Chart 

P.13Ab-22

.

NO :  Go to Step 4.

STEP 4. Retest the system.
Q: Does the accelerator pedal work normally?

YES : The procedure is complete.
NO :  Go to Step 1.

ON-VEHICLE SERVICE

ACCELERATOR PEDAL POSITION SENSOR 
ADJUSTMENT

M1171002600018

Refer to GROUP 13A, On-vehicle Service 

− Accelerator Pedal 

Position Sensor Adjustment 

P.13Aa-12

.

ACCELERATOR PEDAL POSITION SENSOR 
CHECK

M1171001900027

Refer to GROUP 13A, On-vehicle Service 

− Accelerator Pedal 

Position Sensor Check 

P.13Aa-18

.

ACCELERATOR PEDAL POSITION SWITCH 
CHECK

M1171002700015

Refer to GROUP 13A, On-vehicle Service 

− Accelerator Pedal 

Position Switch Check 

P.13Aa-19

.

ACX02258AC

MB991502

16-PIN

ENGINE CONTROL

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ENGINE AND EMISSION CONTROL

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ACCELERATOR CABLE AND PEDAL

REMOVAL AND INSTALLATION

M1171001200277

CAUTION

The accelerator pedal position sensor is preadjusted precisely at factory. Whenever the accelerator 
pedal position sensor is removed and installed, it should be adjusted.

INSTALLATION SERVICE POINT

.

>>A<< ACCELERATOR PEDAL PAD INSTALLATION

CAUTION

To prevent damages to the accelerator pedal pad, warm 
the thumb area of the accelerator pedal pad with a dryer, 
etc. prior to assembling it.
NOTE: If it is difficult to assemble, apply soapy water to the 
thumb area to enhance the assembling process.

Post-installation Operation
Accelerator Pedal Position Sensor Adjustment (Refer to 
GROUP 13A, On-vehicle Service 

P.13Aa-12

.)

AC204064

12 ± 2 N·m
102 ± 22 in-lb

1

2

3

4

5

6

7

8

9

10

N

AB

3.5 ± 1.0 N·m
31 ± 9 in-lb

N

5

11

REMOVAL STEPS

1. ACCELERATOR PEDAL POSITION 

SENSOR

2. ACCELERATOR PEDAL ASSEMBLY
3. PUSH-ON SPRING NUT
4. ACCELERATOR PEDAL PAD AND 

ACCELERATOR ARM ASSEMBLY

5. BUSHING

6. SPRING
7. STOPPER
8. ACCELERATOR PEDAL BRACKET

>>A<<

9. ACCELERATOR PEDAL PAD
10. ACCELERATOR ARM
11. ACCELERATOR STOPPER

REMOVAL STEPS (Continued)