ignition ISUZU TF SERIES 2004 Workshop Manual

6A-10 ENGINE MECHANICAL (6VE1 3.5L)
Engine Lacks Power
Symptom Possible Cause Action
Trouble in fuel system Fuel Pressure Control Valve not
working normally Replace
Fuel injector clogged Clean or replace
Fuel pipe clogged Clean
Fuel filter clogged or fouled Replace
Fuel pump drive circuit not working
normally Correct or replace
Fuel tank not sufficiently breathing
due to clogged Evaporative Emission
Control System circuit Clean or replace
Water in fuel system Clean
Inferior quality fuel in fuel system Use fuel of specified octane rating
Engine Control Module supplied poor
voltage Correct circuit
Throttle Position Sensor cable broken
or poor connections Correct or replace
Throttle Position Sensor defective Replace
Mass Airflow Sensor not working
normally Replace
Manifold Absolute Pressure Sensor
not working normally Replace
Intake Air Temperature Sensor not
working normally Replace
Engine Coolant Temperature Sensor
circuit open or shorted Correct or replace
Engine Coolant Temperature Sensor
defective Replace
Engine Control Module defective Replace
Trouble in intake or exhaust system Air Cleaner Filter clogged Replace filter element
Air duct kinked or flattened Correct or replace
Exhaust system clogged Correct or replace
Ignition failure ———— Refer to Hard Start Troubleshooting
Guide
Heat range of spark plug inadequateInstall spark plugs of adequate heat
range
Ignition coil defective Replace

6A-14 ENGINE MECHANICAL (6VE1 3.5L)
Troubleshooting Procedure
The slapping sound stops when spark plug on bad
cylinder is shorted out.

Symptom Possible Cause Action
Timing belt noise Timing belt tension is incorrect Replace pusher or adjust the tension
pulley or replace timing belt
Tensioner bearing defective Replace
Timing belt defective Replace
Timing pulley defective Replace
Timing belt comes in contact with
timing cover Replace timing belt and timing cover
Valve noise Valve clearance incorrect Replace adjusting shim
Valve and valve guide seized Replace valve and valve guide
Valve spring broken or weakened Replace
Valve seat off–positioned Correct
Camshaft worn out Replace
Crankshaft noise Crankshaft end play excessive (noise
occurs when clutch is engaged) Replace thrust bearing
Engine knocking Preignition due to use of spark plugs
of inadequate heat range Install Spark Plugs of adequate heat
range
Carbon deposits in combustion
chambers Clean
Fuel too low in octane rating Replace fuel
Wide Open Throttle enrichment
system failure Refer to Section 6E
Selection of transmission gear
incorrect Caution operator of incorrect gear
selection
Engine overheating Refer to “Engine Lacks Power"
Others Water pump defective Replace
Drive belt slipping Replace auto tentioner or drive belt

6A-16 ENGINE MECHANICAL (6VE1 3.5L)
Symptom Possible Cause Action
Trouble in emission control system Heated Oxygen Sensor circuit open Correct or replace
Heated Oxygen Sensor defective Replace
Signal vacuum hose loosely fitted or
defective Correct or replace
EGR Valve circuit open or shorted Correct or replace
EGR Valve defective Replace
ECT Sensor circuit open or shorted Correct or replace
Canister Purge Valve circuit open or
shorted Correct or replace
Canister Purge Valve defective Replace
ECT Sensor defective Replace
Positive Crankcase Ventilation (PCV)
valve and hose clogged Correct or replace
Evaporator system Refer to Section 6E
Trouble in ignition system ———— Refer to “Engine Lacks Power"
Trouble in cylinder head parts Carbon deposits in combustion
chamber Remove carbon
Carbon deposit on valve, valve seat
and valve guide Remove carbon

6A-18 ENGINE MECHANICAL (6VE1 3.5L)
Fuel Consumption Excessive
Symptom Possible Cause Action
Trouble in fuel system Mixture too rich or too lean due to
trouble in fuel injection system Refer to “Abnormal Combustion"
Fuel cut function does not work Refer to “Abnormal Combustion"
Trouble in ignition system Misfiring or abnormal combustion due
to trouble in ignition system Refer to “Hard Start" or “Abnormal
Combustion"
Others Engine idle speed too high Reset to Section 6E
Returning of accelerator control
sluggish Correct
Fuel system leakage Correct or replace
Clutch slipping Correct
Brake drag Correct
Selection of transmission gear
incorrect Caution operator of incorrect gear
selection
Lubrication Problems
Symptom Possible Cause Action
Oil pressure too low Wrong oil in use Replace with correct engine oil
Relief valve sticking Replace
Oil pump not operating properly Correct or replace
Oil pump strainer clogged Clean or replace strainer
Oil pump worn Replace
Oil pressure gauge defective Correct or replace
Crankshaft bearing or connecting rod
bearing worn Replace
Oil contamination Wrong oil in use Replace with correct engine oil
Oil filter clogged Replace oil filter
Cylinder head gasket damage Replace gasket
Burned gases leaking Replace piston and piston rings or
cylinder body assembly
Oil not reaching valve system Oil passage in cylinder head or
cylinder body clogged Clean or correct

ENGINE MECHANICAL (6VE1 3.5L) 6A-21
Cylinder Head Cover LH
Removal
1. Disconnect battery ground cable.
2. Disconnect positive crankcase ventilation hose.
3. Remove camshaft angle sensor connector.
4. Remove ground cable fixing bolt on cylinder head
cover.
5. Ignition coil connector and ignition coil.

Disconnect the three connectors from the
ignition coils.

Remove harness bracket bolt on cylinder head
cover.

Remove fixing bolts on ignition coils.









060RW078
Legend
(1) Ignition Coil Connector
(2) Bolt
(3) Ignition Coil Assemblies

6. Remove fixing bolt for fuel injector harness
bracket.

7. Remove eight fixing bolts, then the cylinder head
cover.






010RW001
Installation
1. Install cylinder head cover.

Clean the sealing surface of cylinder head and
cylinder head cover to remove oil and sealing
materials completely.

Apply sealant (TB-1207B or equivalent) of bead
diameter 2-3 mm at eight place of arched area
of camshaft bracket on front and rear sides.

The cylinder head cover must be installed with
in 5 minutes after sealant application to preven
t
hardening of sealant.

Tighten bolts to the specified torque.
Torque : 9 N




m (0.9 kg




m/7 lb ft)




010RW006

6A-22 ENGINE MECHANICAL (6VE1 3.5L)
2. Install fuel injection harness bracket and tighten
bolt to the specified torque.
Torque : 8 N




m (0.8 kg




m/8 lb ft)
3. Connect ignition coil connector and ignition coil,
then tighten bolt to the specified torque.
Torque : 4 N




m (0.4 kg




m/3 lb ft)


060RW078
Legend
(1) Ignition Coil Connector
(2) Bolt
(3) Ignition Coil Assembly

4. Connect ground cable and tighten bolts to the
specified torque.
Torque : 8 N




m (0.8 kg




m/6 lb ft)
5. Connect camshaft angle sensor connector.
6. Install positive crankcase ventilation hose.

ENGINE MECHANICAL (6VE1 3.5L) 6A-23
Cylinder Head Cover RH
Removal
1. Disconnect battery ground cable.
2. Remove air cleaner duct assembly.
3. Disconnect ventilation hose from cylinder head
cover.
4. Disconnect three ignition coil connectors from
ignition coils and remove harness bracket bolts on
cylinder head cover then remove ignition coil fixing
bolts on ignition coils and remove ignition coils.
5. Remove heater pipe fixing bolts from the bracket.
6. Disconnect fuel injector harness connector then
remove fuel injector harness bracket bolt.
7. Remove eight fixing bolts then the cylinder head
cover.





010RW002
Installation
1. Install cylinder head cover.

Clean the sealing surface of cylinder head and
cylinder head cover to remove oil and sealing
materials completely.

Apply sealant (TB-1207B or equivalent) of bead
diameter 2‐3 mm at eight place of arched
area of camshaft bracket on front and rea
r
sides.

The cylinder head cover must be installed
within 5 minutes after sealant application to
prevent premature hardening of sealant.

Tighten bolts to the specified torque.
Torque : 9 N




m (0.9 kg




m/7 lb ft)





014RW019
2. Install exhaust gas recirculation pipe and tighten to
specified torque.
Torque :
Exhaust manifold side: 29 N




m (3.0 kg




m/21 lb ft)
Flare nut: 44 N




m (4.5 kg




m/33 lb ft)
Cylinder head side: 20 N




m (2.0 kg




m/14 lb ft)
3. Tighten fuel injector harness bracket bolts to
specified torque then reconnect fuel injecto
r
harness connector.
Torque : 8 N




m (0.8 kg




m/5.7 lb ft)
4. Install heater pipe bolt to the specified torque.
Torque : 20 N




m (2.0 kg




m/14 lb ft)
5. Connect ignition coil connector and tighten ignition
coil fixing bolts to specified torque.
Torque : 4 N




m (0.4 kg




m/3 lb ft)
6. Connect ventilation hose to cylinder head.
7. Install air cleaner duct assembly.

ENGINE MECHANICAL (6VE1 3.5L) 6A-93
Main Data and Specification

General Specification
Item Specifications
Engine type, number of cylinders and arrangement Water cooled, four cycle V6
Form of combustion chamber Pent-roof type
Valve mechanism 4-Cams, 4-Valves, DOHC Gear & Belt Drive
Cylinder liner type Casted in cylinder block
Total piston displacement 3494 cc
Cylinder bore x stroke 93.4mm x 85.0mm

(3.6772 in  3.3465 in)
Compression ratio 8.6
Compression pressure at 300rpm 1.37 MPa (14.0 Kg/cm2)
Engine idling speed rpm Non adjustable (750)
Valve clearance Intake: 0.28 mm (0.11 in)

Exhaust: 0.30mm (0.12 in)
Oil capacity 5.3 liters
Ignition timing
Non adjustable (12 BTDC at idle rpm)
Spark plug PK16PR11, RC10PYP4, K16PR-P11
Plug gap 1.0 mm – 1.1 mm (0.0394 in – 0.0433 in)

6A-94 ENGINE MECHANICAL (6VE1 3.5L)
Torque Specifications
Ignition coil, Spark plug, Crankshaft angle sensor and Under cover
N
 m (kg
 m/ lb ft)







RTW460LF000101

ENGINE FUEL (6VE1 3.5L) 6C-9




140R100028
Reuse of Quick–Connector
 Replace the port and connector if scratch, dent or
crack is found.
 Remove any dirt build up on the port when installing
the connector. Replace the connector, if there is any
forms of rust, dent, scratch.
 After cleaning the port, insert it straight into the
connector until it clicks. After it clicks, try pulling a
t
49N (5kgf) it out to make sure that it is not drawn
and is securely locked.




140R100036

Assembling Advice
By applying engine oil or light oil to the pipe, port makes
pipe assembly easier. The pipe assembly should take
place immediately after applying oil (to prevent dus
t
from sticking to the pipe surface –which may
decrease sealing ability).
Test/Inspection After Assembling
1. Reconnect the battery negative cable.
2. Turn the ignition key to the “ON" position and listen
for pump start-up sound. Inspect for leaks, the
fuel pressure will increase as the fuel pump is
actuated.
3. Perform leak inspection (step 2) several times.
4. Start the engine and observe the engine idle speed.
The presence of dirt in the fuel system may affec
t
the fuel injection system.