3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-329
SYMPTOM DIAGNOSIS
PRELIMINARY CHECKS
Before using this section, perform the "On-Board
Diagnostic (OBD) System Check" and verify all of the
following items:
The engine control module (ECM) and check engine
lamp (MIL=malfunction indicator lamp) are operating
correctly.
There are no Diagnostic Trouble Code(s) stored.
Tech 2 data is within normal operating range. Refer
to Typical Scan Data Values.
Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time. This check should include the following items:
ECM grounds for cleanliness, tightness and proper
location.
Vacuum hoses for splits, kinks, and proper
connection. Check thoroughly for any type of leak or
restriction.
Air intake ducts for collapsed or damaged areas.
Air leaks at throttle body mounting area, manifold
absolute pressure (MAP) sensor and intake manifold
sealing surfaces.
Ignition wires for cracking, harness, and carbon
tracking.
Wiring for proper connections, pinches and cuts.
INTERMITTENT
Important: An intermittent problem may or may not turn
on the check engine lamp (MIL=malfunction indicato
r
lamp) or store a Diagnostic Trouble Code. Do NOT use
the Diagnostic Trouble Code (DTC) charts fo
r
intermittent problems.
The fault must be present to locate the problem.
Most intermittent problems are cased by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions.
Poor mating of the connector halves or a terminal
not fully seated in the connector (backed out).
Improperly formed or damaged terminal.
All connector terminals in the problem circuit should
be carefully checked for proper contact tension.
Poor terminal-to-wire connection. This requires
removing the terminal form the connector body to
check.
Ignition coils shorted to ground and arcing at ignition
wires or plugs.
Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM shorted to ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Road test the vehicle with a Digital Multimete
r
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication tha
t
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 have several features that can be used to
located an intermittent condition. Use the following
features to find intermittent faults:
To check for loss of diagnostic code memory,
disconnect the mass air flow (MAF) sensor and idle the
engine until the check engine lamp (MIL=malfunction
indicator lamp) comes on. Diagnostic Trouble Code
P0102 should be stored and kept in memory when the
ignition is turned OFF.
If not, the ECM is faulty. When this test is completed,
make sure that you clear the Diagnostic Trouble Code
P0102 from memory.
An intermittent check engine lamp (MIL=malfunction
indicator lamp) with no stored Diagnostic Trouble Code
may be caused by the following:
Ignition coil shorted to ground and arcing at ignition
wires or plugs.
Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM short to ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Check for improper installation of electrical options such
as light, cellular phones, etc. Check all wires from ECM
to the ignition control module for poor connections.
Check for an open diode across the A/C compresso
r
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).
6E-330 3.5L ENGINE DRIVEABILITY AND EMISSIONS
If problem has not been found, refer to ECM connector
symptom tables.
Check the "Broadcast Code" of the ECM, and
compare it with the latest Isuzu service bulletins
and/or Isuzu EEPROM reprogramming equipment to
determine if an update to the ECM's
reprogrammable memory has been released.
To check the "Broadcast Code", connect the Tech 2,
then look for "ID info." then select "Broadcast Code".
This should display a 4 character code, such as "8501"
(example only).
This identifies the contents of the reprogrammable
software and calibration contained in the ECM.
If the "Broadcast Code" is not the most curren
t
available, it is advisable to reprogram the ECM's
EEPROM memory, which may either help identify a
hard-to find problem or may fix the problem.
The Service Programming System (SPS) will not allo
w
incorrect software programming or incorrect calibration
changes.
ENGINE EXHAUST (6VE1 3.5L) 6F-1
ENGINE
ENGINE EXHAUST (6VE1 3.5L)
CONTENTS
Service Precaution................................................. 6F-1
General Description............................................... 6F-2
Three Way Catalytic Converter and Center
Exhaust Pipe.......................................................... 6F-3
Three Way Catalytic Converter and Center
Exhaust Pipe and Associated Parts................ 6F-3
Removal............................................................... 6F-3
Installation............................................................. 6F-3
Exhaust Silencer and Rear Exhaust Pipe........... 6F-4
Exhaust Silencer and Rear Exhaust Pipe and
Associated Parts................................................. 6F-4
Removal................................................................ 6F-4
Installation............................................................. 6F-4
Main Data and Specifications................................ 6F-5
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.
ENGINE LUBRICATION (6VE1 3.5L) 6G-1
ENGINE
ENGINE LUBRICATION (6VE1 3.5L)
CONTENTS
Service Precaution................................................. 6G-1
General Description............................................... 6G-2
Oil Pump.................................................................. 6G-3
Oil Pump and Associated Parts........................ 6G-3
Disassembly........................................................ 6G-4
Inspection and Repair........................................ 6G-4
Reassembly......................................................... 6G-5
Oil Pan and Crankcase.......................................... 6G-7
Removal............................................................... 6G-7
Installation............................................................. 6G-7
Oil Pump.................................................................. 6G-9
Removal................................................................ 6G-9
Installation............................................................. 6G-9
Oil Pump Oil Seal.................................................... 6G-11
Removal................................................................ 6G-11
Installation............................................................. 6G-11
Main Data and Specification.................................. 6G-12
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners o
r
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.
ENGINE SPEED CONTROL SYSTEM (6VE1 3.5L) 6H-1
ENGINE
ENGINE SPEED CONTROL SYSTEM (6VE1 3.5L)
CONTENTS
Service Precaution................................................. 6H-1
Accelerator Pedal Control Cable.......................... 6H-2
Removal............................................................... 6H-2
Inspection............................................................. 6H-2
Installation............................................................ 6H-3
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners o
r
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.
INDUCTION (6VE1 3.5L) 6J-1
ENGINE
INDUCTION (6VE1 3.5L)
CONTENTS
Service Precaution................................................. 6J-1
Air Cleaner Element............................................... 6J-2
Removal............................................................... 6J-2
Inspection............................................................. 6J-2
Installation............................................................. 6J-2
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners o
r
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.
ENGINE DIAGNOSIS (C24SE) 6-1
SECTION 6
ENGINE DIAGNOSIS
CONTENTS
PAGE
Engine Diagnosis............................................................................................................... 6- 2
Hard Starting ................................................................................................................. 6- 2
Engine Compression Test Procedure ......................................................................... 6- 3
Rough Engine Idling or Engine Stalling ...................................................................... 6- 4
Rough Engine Running ................................................................................................ 6- 5
Hesitation....................................................................................................................... 6- 6
Engine Lacks Power ..................................................................................................... 6- 7
Engine Noisy ................................................................................................................. 6- 8
Abnormal Noise Due to Hydraulic Lash Adjustor ...................................................... 6- 9
Troubleshooting Procedure ......................................................................................... 6- 9
Abnormal Combustion.................................................................................................. 6-11
Engine Oil Consumption Excessive ............................................................................ 6-12
Fuel Consumption Excessive ...................................................................................... 6-13
Oil Problems .................................................................................................................. 6-13
Engine Oil Pressure Check .......................................................................................... 6-13
Malfunction Indicator Lamp ......................................................................................... 6-14
ENGINE MECHANICAL (C24SE) 6A-1
SECTION 6A
ENGINE MECHANICAL
CONTENTS
PAGE
General Description......................................................................................................... 6A- 4
ENGINE PICTORIAL .................................................................................................... 6A- 6
Main Data and Specification ........................................................................................... 6A-11
CRANKCASE VENTILATION SYSTEM ....................................................................... 6A-16
ENGINE ASSEMBLY & LOOSE PARTS ..................................................................... 6A-17
OPERATIONS ON ENGINE AGGREGATES .................................................................... 6A-18
Engine Damping Blocks(Engine without Transmission)......................................... 6A-18
Toothed Belt and Timing Check ............................................................................... 6A-21
Toothed Belt Tension, Adjust .................................................................................... 6A-23
Toothed Belt, Replace ................................................................................................ 6A-24
OPERATIONS ON INSTALLED ENGINE ......................................................................... 6A-26
Gasket, Exhaust Manifold, Cylinder Head ................................................................ 6A-26
Gasket, Intake Manifold, Cylinder Head .................................................................... 6A-26
Seal Ring, Camshaft Housing, Timing Side .............................................................. 6A-27
Seal Ring, Thermostat Housing, Cylinder Head ....................................................... 6A-27
Seal Ring - Front Camshaft Housing, Replace ......................................................... 6A-28
Toother Belt Rear Cover ............................................................................................. 6A-30
Toother Belt Tension Roller ....................................................................................... 6A-31
COMPONENT PARTS ...................................................................................................... 6A-32
Cylinder Head .............................................................................................................. 6A-32
Hydraulic Valve Lifter.................................................................................................. 6A-33
OPERATIONS ON CYLINDER HEAD AND CAMSHAFT HOUSING ............................... 6A-34
Camshaft...................................................................................................................... 6A-34
Camshaft Housing Removal and Installation ........................................................... 6A-35
Cylinder Head .............................................................................................................. 6A-35
Hydraulic Valve Lifers, Replace ................................................................................. 6A-37
Camshaft Housing, Replace....................................................................................... 6A-37