ISUZU AXIOM 2002 Service Repair Manual

6E±534
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Bank 2 Restricted Exhaust System Check

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. 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 3Go to Step 4
3Repair the restriction in the exhaust system after the
catalytic converter.
Possible faults include:

Collapsed pipe

Heat distress

Internal muffler failure
Is the action complete?
ÐVerify repairÐ
41. 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
5Repair the restriction in the catalytic converter.
Is the action complete?
ÐVerify repairÐ
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.

6E±535
6VE1 3.5L 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 DiagnosisDefault Section(s)
On-Board Diagnostic (OBD) System
CheckVehicle does not enter diagnostics.Chassis Electrical
On-Board Diagnostic (OBD) System
CheckVehicle enters diagnostics and
communicates with the Tech 2. MIL is
ªONº in diagnostics. Engine does not
start and run.Ignition System Check
On-Board Diagnostic (OBD) System
CheckEngine starts and runs, no PCM
codes set. Customer complains of
vibration.Ð
On-Board Diagnostic (OBD) System
CheckEngine 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 CheckOn-Board Diagnostic (OBD) System
Check.Chassis Electrical
PCM Power and Ground CheckOn-Board Diagnostic (OBD) System
Check. PCM power and ground
circuits OK. Data link voltage
incorrect.Chassis Electrical
On-Board Diagnostic (OBD) System
CheckEngine 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
SymptomsInitial DiagnosisDefault Section(s)
Intermittents1. On-board Diagnostic (OBD)
system check.
2. Careful visual/physical
inspections.Chassis Electrical
Hard Starts1. 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

6E±536
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Symptoms Default Section(s)Initial Diagnosis
Surges and/or Chuggles1. 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 Spongy1. 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 Knock1. 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,
Stalling1. 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 Economy1. OBD system check.
2. Careful visual/physical inspection.
3. Ignition system.
4. Cooling system.TCC Operation, Exhaust System
(refer to
Engine Exhaust)
Hesitation, Sag, Stumble1. 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, Misses1. OBD system check.
2. Cylinder balance test.
3. ETC system check.Ignition System Check
Engine Cranks But Will Not Run1. OBD system check.Fuel System Electrical
Diagnosis, Fuel System
Diagnosis, Fuel Injector and Fuel
Injector Balance Test.

6E±537
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Symptoms Default Section(s)Initial Diagnosis
Excessive Exhaust Emissions or
Odors1. 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. MAP output check.EGR System Check, Exhaust
Diagnosis, Calibration ID/Service
Bulletins
Dieseling, Run-On1. OBD system check.
2. Careful visual/physical inspection.
3. Fuel system diagnosis.Ð
Backfire1. OBD system check.
2. Ignition system.
3. Fuel system diagnosis.
4. Fuel injector and fuel injector
balance test.
5. EGR operation, EGR system
check.Exhaust System Diagnosis,
Intake Casting Flash, Ignition
System Check
Misfire1. OBD system check.
2. Ignition system.
3. Fuel system diagnosis.
4. Fuel injector and fuel injector
balance test.Vibrations, Transmission,
Driveshaft and Axle
Catalyst Monitor1. OBD system check.
2. Careful visual/physical inspection.
3. Heated oxygen sensors.Exhaust System
Fuel Trim1. OBD system check.
2. Careful visual/physical inspection.
3. Fuel system diagnosis.
4. Heated oxygen sensors, MAF
sensors.Exhaust System Intake Air
System
Evaporative Emissions1. OBD system check.
2. Careful visual/physical inspection.
3. Fuel system diagnosis.Ð
Heated Oxygen Sensors1. OBD system check.
2. Careful visual/physical inspection.Exhaust System

6E±538
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
On Vehicle
Service Crankshaft Position
(CKP) Sensor
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the electrical connector to the CKP
sensor.
3. Remove one bolt and the CKP sensor from the right
side of the engine block, just behind the mount.
NOTE: Use caution to avoid any hot oil that might drip
out.
TS22909
Inspection Procedure
1. Inspect the sensor O-ring for cracks or leaks.
2. Replace the O-ring if it is worn or damaged.
3. Lubricate the new O-ring with engine oil.
4. Install the lubricated O-ring.
Installation Procedure
1. Install the CKP sensor in the engine block.
2. Install the CKP sensor mounting bolt.
Tighten

Tighten the mounting bolt to 9 N´m (78 lb in.).
TS22909
3. Connect the electrical connector to the CKP sensor.
4. Connect the negative battery cable.
Engine Coolant Temperature
(ECT) Sensor
Removal Procedure
NOTE: Care must be taken when handling the engine
coolant temperature (ECT) sensor. Damage to the ECT
sensor will affect proper operation of the fuel injection
system.
1. Disconnect the negative battery cable.
2. Drain the radiator coolant. Refer to
Draining and
Refilling Cooling System
in Engine Cooling section.
3. Disconnect the electrical connector.
014RY00001

6E±539
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
4. Remove the ECT sensor from the coolant crossover.
014RY00002
Installation Procedure
1. Apply sealer or the equivalent to the threads of the
ECT sensor.
2. Install the ECT sensor in the coolant crossover.
Tighten

Tighten the ECT sensor to 30 N´m (22 lb ft.).
014RY00002
3. Connect the electrical connector.
014RY00003
4. Fill the radiator with coolant. Refer to Draining and
Refilling Cooling System
in Engine Cooling section.
5. Connect the negative battery cable.
Heated Oxygen Sensor (HO2S)
Removal Procedure
1. Disconnect the negative battery cable.
2. Locate the four oxygen sensors.
060RW008

6E±540
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Bank 1 sensor 1 is mounted on the exhaust pipe
ahead of the right-hand catalytic converter.
TS22912

Bank 1 sensor 2 is mounted behind the right-hand
catalytic converter.
TS22913

Bank 2 sensor 1 is mounted on the exhaust pipe
ahead of the left-hand catalytic converter.
TS22914

Bank 2 sensor 2 is mounted behind the left-hand
catalytic converter.
TS22915

6E±541
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
3. Disconnect the pigtail from the wiring harness.
060RY00128
IMPORTANT:The pigtail is permanently attached to
the sensor. Be careful not to pull the wires out.
NOTE: Do not use a torch to remove an HO2S unless the
sensor is being replaced. Using a torch could damage the
sensor.
4. Remove the sensor from the exhaust pipe.

Because of the expansion and contraction of the
metal in the exhaust system over time, this may be
difficult if the engine temperature is below 48
C
(120
F).
060RY00128
Inspection Procedure
All four sensors are identical. Inspect each in the same
way.
1. Inspect the pigtail and the electrical connector for
grease, dirt, corrosion, and bare wires or worn
insulation.
2. Inspect the louvered end of the sensor for grease,
dirt, or other contaminations.
060RY00128
Installation Procedure
IMPORTANT:

There is a special anti-seize compound on the HO2S
threads. This compound consists of glass beads
suspended in a liquid graphite solution. The graphite
burns away with engine heat, but the glass beads will
remain, making the sensor easier to remove.

New or service sensors will already have the
compound applied to the threads. If a sensor is
removed and is to be reinstalled for any reason, the
threads must have anti-seize compound applied.
1. Apply anti-seize compound or the equivalent to the
threads of the oxygen sensor, if necessary.
2. Install the oxygen sensor on the exhaust pipe in its
original position.
Tighten

Tighten the oxygen sensor to 55 N´m (40 lb ft.).
060RY00128
3. Connect the pigtail to the wiring harness.
4. Connect the negative battery cable.

6E±542
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Intake Air Temperature (IAT)
Sensor
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the engine cover
3. The IAT sensor is located in the intake air duct, behind
the throttle body.
4. Disconnect the electrical connector from the IAT
sensor.
TS23741
5. Remove the IAT sensor from the intake air duct by
using a rocking motion while pulling the sensor.
Installation Procedure
1. Install the IAT sensor into the grommet in the intake
air duct.
2. Correct the IAT electrical connector.
TS23741
3. Install the engine cover.
4. Connect the negative battery cable.
ION Sensing Module
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the ION sensing module connector.
3. Remove the bolts and the ION sensing module from
the common chamber.
060RY00087
Installation Procedure
1. Install the ION sensing module on the common
chamber with the bolts.
Tighten

Tighten the ION sensing module to 4 N´m (35 lb
in.).

6E±543
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
2. Connect the ION sensing module connectors as
shown in the illustration.
060RY00003
Legend
(1) Green Color Connector
(2) Blue Color Connector
3. Connect the negative battery cable.
Mass Air Flow (MAF) Sensor
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the electrical connector from the MAF
sensor.
TS23740
3. Loosen the clamps which secure the intake air duct
and the air cleaner to the MAF sensor.4. Remove the intake air duct from the MAF sensor.
5. Remove the MAF sensor from the air cleaner.
TS23781
Installation Procedure
1. Install the MAF sensor on the air cleaner with the
clamp.
2. Install the intake air duct and the clamp on the MAF
sensor.
TS23781
3. Tighten the clamps to secure the MAF sensor to the
intake air duct and the air cleaner.
4. Connect the MAF electrical connector.
5. Connect the negative battery cable.