Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1519

6E2–527

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Bank 1 Restricted Exhaust System Check

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Remove the Bank 1 HO2S 2.
2. Install the Exhaust Backpressure Tester

(BT-8515-V or equivalent) in place of the Bank 1
HO2S 2.

3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow

10 seconds for pressure to build.

5. Observe the exhaust system backpressure reading

on the gauge.

Does the reading exceed the amount in the value
column?

8.62 kPa

(1.25 psi)

Go to 

Step 3

Go to 

Step 4

3

Repair the restriction in the exhaust system after the
catalytic converter.
Possible faults include:

D

Collapsed pipe

D

Heat distress

D

Internal muffler failure

Is the action complete?

—

Verify repair

—

4

1. Install the Bank 1 HO2S 2.
2. Install the Exhaust Backpressure Tester in place of

Bank 1 HO2S 1.

3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow

10 seconds for pressure to build.

5. Observe the exhaust system backpressure reading

on the gauge.

Does the reading exceed the amount in the value
column?

8.62 kPa

(1.25 psi)

Go to 

Step 5

No trouble

found.  If a
driveability

symptom

exists, refer
to symptom

charts

5

Repair the restriction in the catalytic converter.

Is the action complete?

—

Verify repair

—

NOTE: DTCs will be set by running the vehicle to normal
operating temperature after a cold start with the O2
sensor disconnected.  After performing these tests, use
the Tech 2 to erase the DTCs that were set by the lack of
O2 sensor activity.

6E2–528

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Bank 2 Restricted Exhaust System Check

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Remove the Bank 2 HO2S 2.
2. Install the Exhaust Backpressure Tester

(BT-8515-V or equivalent) in place of the Bank 2
HO2S 2.

3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow

10 seconds for pressure to build.

5. Observe the exhaust system backpressure reading

on the gauge.

Does the reading exceed the amount in the value
column?

8.62 kPa

(1.25 psi)

Go to 

Step 3

Go to 

Step 4

3

Repair the restriction in the exhaust system after the
catalytic converter.
Possible faults include:

D

Collapsed pipe

D

Heat distress

D

Internal muffler failure

Is the action complete?

—

Verify repair

—

4

1. Install the Bank 2 HO2S 2.
2. Install the Exhaust Back pressure Tester in place of

Bank 1 HO2S 1.

3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow

10 seconds for pressure to build.

5. Observe the exhaust system backpressure reading

on the gauge.

Does the reading exceed the amount in the value
column?

8.62 kPa

(1.25 psi)

Go to 

Step 5

No trouble

found.  If a
driveability

symptom

exists, refer
to symptom

charts

5

Repair the restriction in the catalytic converter.

Is the action complete?

—

Verify repair

—

NOTE: DTCs will be set by running the vehicle to normal
operating temperature after a cold start with the O2
sensor disconnected.  After performing these tests, use
the Tech 2 to erase the DTCs that were set by the lack of
O2 sensor activity.

6E2–529

RODEO 6VD1 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 PCM
codes set.  Customer complains of
vibration.

—

On-Board Diagnostic (OBD) System
Check

Engine starts and runs, no PCM
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

PCM Power and Ground Check

On-Board Diagnostic (OBD) System
Check.

Chassis Electrical

PCM Power and Ground Check

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

Chassis Electrical

On-Board Diagnostic (OBD) System
Check

Engine starts and runs, no PCM
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. ETC system check.
3. Sensors (ECT, MAP, MAF, TP) ;

MAP output chart.

4. Fuel system electrical test, fuel

system diagnosis.

5. Ignition system.

Engine Mechanical, Ignition
System Check, Exhaust System
Diagnosis

6E2–530

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Symptoms

Default Section(s)

Initial Diagnosis

Surges and/or Chuggles

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

Calibration ID/Service Bulletins,
Ignition System Check,
Generator Output, Exhaust
System Diagnosis, 4L30-E
System Test

Lack of Power, Sluggish or Spongy

1. OBD system check.
2. ETC system check.
3. Fuel system diagnosis.
4. Ignition system.
5. EGR operation.
6. EGR system check.

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. EGR operation.
4. EGR system check.
5. TCC operation.
6. Fuel system diagnosis.
7. Ignition system.
8. ION sensing module check.

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

Rough, Unstable, or Incorrect Idle,
Stalling

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

balance test.

4. EVAP emission canister purge

valve check.

5. Ignition system.
6. EGR operation.

MAP Output Check, Throttle
Linkage, EGR 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)

Hesitation, Sag, Stumble

1. OBD system check.
2. ETC system check.
3. TP.
4. MAP output check.
5. Fuel system diagnosis.
6. Fuel injector and fuel injector

balance test.

7. EVAP emission canister purge

valve.

8. Ignition system.

EGR Operation, EGR System
Check, 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.
3. ETC system check.

Ignition System Check

Engine Cranks But Will Not Run

1. OBD system check.

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