Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 871

6E–213

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Hesitation, Sag, Stumble Symptom

  (Cont'd)

Step

No

Yes

Value(s)

Action

10

1. Check for proper ignition voltage output with spark

tester J 26792 (ST-125).  Refer to 

Electronic Ignition

System for the procedure.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 11

11

1. Check for a loose ignition coil ground.

Refer to 

Electronic Ignition System.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 12

12

1. Check the ignition coils for cracks or carbon

tracking.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 13

13

1. Remove spark plugs and check for wet plugs,

cracks, wear, improper gap, burned electrodes, or
heavy deposits.  Refer to 

Electronic Ignition

System.

NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 14

14

1. Check the ECM grounds for clearness, tightness

and proper routing.  Refer to the ECM wiring
diagrams in Electrical Diagnosis.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 15

15

1. Check the MAF sensor connections.
2. If a problem is found, replace the faulty terminals as

necessary.  Refer to 

Electrical Diagnosis for wiring

repair procedures.

Was a problem found?

—

Verify repair

Go to 

Step 16

16

1. Visually/physically check vacuum hoses for splits,

kinks, and proper connections and routing as
shown on the “Vehicle Emission Control
Information” label.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 17

6E–214 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Hesitation, Sag, Stumble Symptom

  (Cont'd)

Step

No

Yes

Value(s)

Action

17

1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no

malfunctions have been found, review/inspect the
following:

D

Visual/physical inspection

D

Tech 2 data

D

Freeze Frame data/Failure Records butter

D

All electrical connections within a suspected
circuit and/or system

3. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Contact

Technical

Assistance

18

Replace the TP sensor.

Is the action complete?

—

Verify repair

—

6E–215

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Default Matrix Table

Service Procedure Default Strategy

A referral strategy has been established to assist the
technician with additional information when the cause of
the failure cannot be determined.  If no problem is found
after performing diagnostics, then refer to the default
matrix table for further diagnostic information.

Default Matrix Table

Strategy Based Diagnostic Charts

Initial Diagnosis

Default Section(s)

On-Board Diagnostic (OBD) System
Check

Vehicle does not enter diagnostics.

Chassis Electrical

On-Board Diagnostic (OBD) System
Check

Vehicle enters diagnostics and
communicates with the Tech 2.  MIL is
“ON” in diagnostics.  Engine does not
start and run.

Ignition System Check

On-Board Diagnostic (OBD) System
Check

Engine starts and runs, no ECM codes
set.  Customer complains of vibration.

—

On-Board Diagnostic (OBD) System
Check

Engine starts and runs, no ECM codes
set.  Customer complains of harsh or
soft shift, poor performance, delayed or
no engagement into drive or reverse,
transmission fluid leak, transmission
noise or vibration, or improper TCC
operation.

Automatic Transmission

ECM Power and Ground Check

On-Board Diagnostic (OBD) System
Check.

Chassis Electrical

ECM Power and Ground Check

On-Board Diagnostic (OBD) System
Check. ECM power and ground circuits
OK. Data link voltage incorrect.

Chassis Electrical

On-Board Diagnostic (OBD) System
Check

Engine starts and runs, no ECM codes
set.  Customer complains of harsh or
soft shift, poor performance, delayed or
no engagement into drive or reverse,
transmission fluid leak, transmission
noise or vibration, or improper TCC
operation.

Automatic Transmission

Symptoms

Initial Diagnosis

Default Section(s)

Intermittents

1. On-board diagnostic (OBD)

system check.

2. Careful visual/physical inspections.

Chassis Electrical

Hard Starts

1. OBD system check.
2. Sensors (ECT, BARO, MAF, TP) ;

BARO output chart.

3. Fuel system electrical test, fuel

system diagnosis.

4. Ignition system.
5. IAC system check.

Engine Mechanical, Ignition
System Check, Exhaust System
Diagnosis

Surges and/or Chuggles

1. OBD system check.
2. Heated oxygen sensors.
3. Fuel system diagnosis.
4. Ignition system.

Calibration ID “Broadcast”
/Service Bulletins, Ignition
System Check, Generator
Output, Exhaust System
Diagnosis

6E–216 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Lack of Power, Sluggish or Spongy

1. OBD system check.
2. Fuel system diagnosis.
3. Ignition system.

Refer to 

Exhaust System in

Engine Exhaust, TCC
Operation, Calibration
ID/Service Bulletins

Detonation/Spark Knock

1. OBD system check.
2. Transmission range switch.
3. TCC operation.
4. Fuel system diagnosis.
5. Ignition system.

TCC operation, Cooling System,
Ignition System Check,
Calibration ID/Service Bulletins

Hesitation, Sag, Stumble

1. OBD system check.
2. TP.
3. BARO output check.
4. Fuel system diagnosis.
5. EVAP emission canister purge

valve.

6. Ignition system.

Generator Output Voltage (refer
to 

Chassis Electrical),

Calibration ID/Service Bulletins,
Ignition System Check

Cuts Out, Misses

1. OBD system check.
2. Cylinder balance test.

Ignition System Check

Rough, Unstable, or Incorrect Idle,
Stalling

1. OBD system check.
2. Fuel injector and fuel injector

balance test.

3. EVAP emission canister purge

valve check.

4. Ignition system.
5. IAC operation.

BARO Output Check, Throttle
Linkage, IAC System Check,
A/C Clutch Control Circuit
Diagnosis, Crankcase
Ventilation System, Calibration
ID/Service Bulletins, Generator
Output Voltage (refer to 

Chassis

Electrical), Exhaust Diagnosis

Poor Fuel Economy

1. OBD system check.
2. Careful visual/physical inspection.
3. Ignition system.
4. Cooling system.

TCC Operation, Exhaust
System (refer to 

Engine

Exhaust)

Engine Cranks But Will Not Run

1. OBD system check.

Fuel System Electrical
Diagnosis, Fuel System
Diagnosis, Fuel Injector and
Fuel Injector Balance Test.

Excessive Exhaust Emissions or
Odors

1. OBD system check.
2. Emission test.
3. Cooling system.
4. Fuel system diagnosis.
5. Fuel injector and fuel injector

balance test.

6. EVAP emission canister purge

valve.

7. Crankcase ventilation system.
8. Ignition system.
9. BARO output check.

Exhaust Diagnosis, Calibration
ID/Service Bulletins

Dieseling, Run-On

1. OBD system check.
2. Careful visual/physical inspection.
3. Fuel system diagnosis.

—

Backfire

1. OBD system check.
2. Ignition system.
3. Fuel system diagnosis.
4. Fuel injector and fuel injector

balance test.

Exhaust System Diagnosis,
Intake Casting Flash, Ignition
System Check