2004 ISUZU TF SERIES air filter

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–413
EXCESSIVE BLACK SMOKE
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check
2 1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?—Verify repair Go to Step 3
3 Was a visually/physical check performed?
—Go to Step 4Go to Visual /
physical Check
4 Is the customer using the incorrect fuel type? Diesel fuel
onlyReplace with
diesel fuel Go to Step 5
5 Visually/physically inspect for the following conditions.
Restrict air intake system. Check for a restricted air
filter element, or foreign objects blocking the air
intake system
Check for objects blocking or ex cessive deposits in
the throttle bore and on the throttle plate
Check for a condition that causes a large vacuum
leak, such as an incorrectly installed or faulty
crankcase ventilation hose.
Restrict air intake system at the turbocharger.
Check for objects blocking the turbocharger
compressor wheel or turbine shaft sticking.
If a problem is found, repair as necessary.
Was a problem found?—Verify repair Go to Step 6
6 Check the ECM & PSG grounds to verify that they are
clean and tight. Refer to the ECM wiring diagrams.
Was a problem found?—Verify repair Go to Step 7
7 1. Using the Tech 2, display the ECT sensor and IAT
sensor value.
2. Check the displayed value.
Does the Tech 2 indicate correct temperature
depending on engine condition?
If a problem is found, repair as necessary.
Was the problem found?—Verify repair Go to Step 8
8 1. Using the Tech 2, display the FT sensor value.
2. Check the displayed value.
Does the Tech 2 indicate correct temperature
depending on engine condition?
If a problem is found, repair as necessary.
Was the problem found?—Go to Step 21Go to Step 9
9 1. Using the Tech 2, ignition “On” and engine “Run”.
2. Monitor the “Mass Air Flow” in the data display.
Does the Tech 2 indicate correct “Mass Air Flow”
depending on accelerator pedal operation? —Go to Step 14Go to Step 10

6A-6 ENGINE MECHANICAL (6VE1 3.5L)
Rough Engine Idling or Engine Stalling
Symptom Possible Cause Action
Trouble in fuel injection system Idle air control valve defective Replace
Throttle shutting off incomplete Replace
Throttle position sensor circuit open
or shorted Correct or replace
Fuel injector circuits open or shortedCorrect or replace
Fuel injectors damaged Replace
Fuel pump relay defective Replace
Mass Airflow Sensor circuit open or
poor connections Correct or replace
Mass Airflow Sensor defective Replace
Engine Coolant Temperature Sensor
circuit open or poor connections Correct or replace
Engine Coolant Temperature Sensor
defective Replace
Intake Air Temperature sensor circuit
open or poor connections Correct or replace
Intake Air Temperature sensor
defective Replace
Vehicle Speed Sensor circuit open or
shorted Correct or replace
Vehicle Speed Sensor defective Replace
Trouble in emission control system EGR valve defective Replace
EGR valve circuit open or poor
connection Correct or replace
Engine Control Module defective Replace
Canister purge valve circuit open or
poor connections Correct or replace
Canister purge valve defective Replace
Evaporative Emission Canister Purge
control valve defective Replace
Trouble in ignition system Refer to “Hard Start"
Others Engine lacks compression Refer to “Hard Start"
Valve incorrectly seated Lap valve
Air Cleaner Filter clogged Replace filter element
Valve timing incorrect Readjust
Idle air control valve broken Replace
Fast idle solenoid defective Replace
Positive Crankcase Ventilation valve
defective or clogged Replace

6A-8 ENGINE MECHANICAL (6VE1 3.5L)
Hesitation
Symptom Possible Cause Action
Hesitation on acceleration Throttle Position Sensor adjustment
incorrect Replace throttle valve assembly
Throttle Position Sensor circuit open
or shorted Correct or replace
Excessive play in accelerator linkageAdjust or replace
Mass Airflow Sensor circuit open or
poor connections Correct or replace
Mass Airflow Sensor defective Replace
Intake Air Temperature (IAT) Sensor
circuit open or poor connections Correct or replace
IAT Sensor defective Replace
Hesitation at high speeds
(Fuel pressure too low) Fuel tank strainer clogged Clean or replace
Fuel pipe clogged Clean or replace
Fuel filter clogged Replace
Defective fuel pump system Check and replace
Fuel Pressure Control Valve leaking Replace
Hesitation at high speeds
(Fuel injector not working normally) Power supply or ground circuit for
Multiport Fuel Injection System
shorted or open Check and correct or replace
Fuel Injector defective Replace
Cable of Multiport Fuel Injection
System circuit open or poor
connections Correct or replace

ENGINE MECHANICAL (6VE1 3.5L) 6A-9
Symptom Possible Cause Action
Hesitation at high speeds Engine Control Module defective Replace
Throttle Position Sensor cable broken
or poor connections Correct or replace
Throttle Position Sensor defective Replace
Engine Coolant Temperature Sensor
circuit open or shorted Correct or replace
Engine Coolant Temperature Sensor
defective Replace
Mass Airflow Sensor circuit open or
poor connections Correct or replace
Mass Airflow Sensor defective Replace
IAT Sensor circuit open or poor
connections Correct or replace
IAT Sensor defective Replace
Throttle valve not fully opened Check and correct or replace
Air Cleaner Filter clogged Replace filter element
Power supply voltage too low Check and correct or replace

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

ENGINE MECHANICAL (6VE1 3.5L) 6A-15
Abnormal Combustion
Symptom Possible Cause Action
Trouble in fuel system Fuel pressure control valve defectiveReplace
Fuel filter clogged Replace
Fuel pump clogged Clean or replace
Fuel tank or fuel pipe clogged Clean or replace
Fuel injector clogged Clean or replace
Fuel pump relay defective Replace
Power supply cable for fuel pump
broken or poor connections Reconnect, correct or replace
Mass Airflow (MAF) Sensor circuit
open or defective Correct or replace
MAF Sensor defective Replace
Engine Coolant Temperature (ECT)
Sensor circuit open or shorted Correct or replace
ECT Sensor defective Replace
Throttle Position Sensor adjustment
incorrect Readjust
Throttle Position Sensor defective Replace
Throttle Position Sensor connector
poor connections Reconnect
Vehicle Speed Sensor cable poor
connections or defective Correct or replace
Vehicle Speed Sensor loosely fixed Fix tightly
Vehicle Speed Sensor in wrong
contact or defective Replace
Engine Control Module cable poor
connections or defective Correct or replace

ENGINE FUEL (6VE1 3.5L) 6C-1
ENGINE
ENGINE FUEL (6VE1 3.5L)
CONTENTS

Service Precaution................................................. 6C-1
General Description............................................... 6C-2
Fuel Metering.......................................................... 6C-3
Fuel Filter................................................................. 6C-4
Removal............................................................... 6C-4
Inspection............................................................. 6C-4
Installation............................................................ 6C-4
Inspection............................................................. 6C-4
In-Tank Fuel Filter............................................... 6C-4
Fuel Pump Flow Test......................................... 6C-4
Fuel Pump............................................................... 6C-6
Fuel Pump and Associated Parts..................... 6C-6
Removal............................................................... 6C-6
Installation............................................................ 6C-7
Fuel Tube / Quick - Connector Fittings............... 6C-8
Precautions.......................................................... 6C-8
Cautions During Work........................................ 6C-8

Removal................................................................ 6C-8
Reuse of Quick-Connector................................. 6C-9
Assembling Advice.............................................. 6C-9
Fuel Pump Relay..................................................... 6C-10
General Description............................................ 6C-10
Fuel Tank................................................................. 6C-11
Fuel Tank and Associated Parts....................... 6C-11
Removal................................................................ 6C-11
Installation............................................................. 6C-12
Filler Neck................................................................ 6C-13
Removal................................................................ 6C-13
Installation............................................................. 6C-13
Fuel Gauge Unit...................................................... 6C-13
Removal and Installation.................................... 6C-13
Fuel Filler Cap......................................................... 6C-14
General Description............................................ 6C-14
Inspection............................................................. 6C-14
Main Data and Specifications................................ 6C-15
Special Tool.......................................................... 6C-16


Service Precaution
When working on the fuel system, there are several
things to keep in mind:
 Any time the fuel system is being worked on,
disconnect the negative battery cable except
for those tests where battery voltage is
required.
 Always keep a dry chemical (Class B) fire
extinguisher near the work area.
 Replace all pipes with the same pipe and
fittings that were removed.
 Clean and inspect “O" rings. Replace i
f
required.
 Always relieve the line pressure before
servicing any fuel system components.
 Do not attempt repairs on the fuel system until
you have read the instructions and checked
the pictures relating to that repair.
 Adhere to all Notices and Cautions.


All gasoline engines are designed to use only
unleaded gasoline. Unleaded gasoline must be
used for proper emission control system operation.
Its use will also minimize spark plug fouling and
extend engine oil life. Using leaded gasoline can
damage the emission control system and could
result in loss of emission warranty coverage.
All cars are equipped with an Evaporative Emission
Control System. The purpose of the system is to
minimize the escape of fuel vapors to the
atmosphere.

6C-2 ENGINE FUEL (6VE1 3.5L)
General Description







RTW36CLF000301
Legend (8) Fuel Rail Left
(1) Fuel Filler Cap (9) Intake Air Port Left Bank
(2) Fuel Tank (10) Fuel Pressure Control Valve
(3) Rollover Valve (11) Common Chamber
(4) Fuel Pump and Sender Assembly (12) Duty Solenoid Valve
(5) Fuel Filter (13) Throttle Valve
(6) Fuel Rail Right (14) Canister
(7) Intake Air Port Right Bank (15) Evapo Control Valve