2004 ISUZU TF SERIES ignition

6E–404 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
20 Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?—Go to Step 21Go to Step 31
21 Replace the MAF & IAT sensor assembly.
Is the action complete?—Veri fy repai r—
22 1. Using the Tech 2, ignition “On” and engine “Off”.
2. Monitor the “Pedal/Throttle Position” and “Idle
Switch” in the data display.
Does the Tech 2 indicate correct “Pedal/Throttle
Position” from 0% to 100% and correct “Idle Switch”
status depending on accelerator pedal operation?—Go to Step 27Go to Step 23
23 1. Using the Tech 2, ignition “On” and engine “Off”.
2. Monitor the “Pedal/Throttle Position” and “Idle
Switch” in the data display.
3. Adjust the accelerator cable or TPS within 0% to
100%.
Was the problem solved?—Verify repair Go to Step 24
24 Check the TPS harness for the following conditions.
Check for poor connector connection.
Check for misrouted harness.
Check for any accessory parts which may cause
electric interference.
If a problem is found, repair as necessary.
Was a problem found? —Verify repair Go to Step 25
25 Substitute a known good TPS and recheck.
Was the problem solved?—Go to Step 26Go to Step 31
26 Replace the TPS.
Is the action complete?—Veri fy repai r—
27 Remove the injection nozzles from the engine and
check for the following conditions.
Improper splay condition.
Operating pressure is incorrect.
If a problem is found, repair as necessary.
Was the problem found?
—Replace the
injection nozzle
and verify repair Go to Step 28 Step Action Value(s) Yes No
1st Stage 2nd Sta ge
4JA1-TCApproximatly
19.0 MpaApprox ima tly
33.5 Mpa
4JH1-TCApproximatly
19.5 MpaApprox ima tly
33.8 Mpa

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–407
EXCESSIVE WHITE 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 Check the engine coolant consumption to verify that it
leaks to combustion chamber or ex haust through the
gasket.
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 30Go 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
10 Remove the MAF & IAT sensor assembly and check
for the following conditions.
Objects blocking at the MAF sensor element.
If a problem is found, repair as necessary.
Was the problem found?—Verify repair Go to Step 11
11 Check the MAF sensor harness for the following
conditions.
Check for poor connector connection.
Check for misrouted harness.
Check for any accessory parts which may cause
electric interference.
If a problem is found, repair as necessary.
Was a problem found? —Verify repair Go to Step 12

6E–408 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
12 Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?—Go to Step 13Go to Step 30
13 Replace the MAF & IAT sensor assembly.
Is the action complete?—Veri fy repai r—
14 1. Using the Tech 2, ignition “On” and engine “Run”.
2. Monitor the “Glow Time Relay” in the data display.
Does the Tech 2 indicate correct “Glow Time Relay”
status depending on the time from engine “Run”?
If a problem is found, repair as necessary.
Was the problem found?—Go to Step 30Go to Step 15
15 1. Using the Tech 2, ignition “On” and engine “Run”.
2. Monitor the “Glow Time Relay” in the data display
and then, does the supply voltage correctly supply
to the glow plug?
—Go to Step 16Repair voltage
supply circuit
and verify repair
16 Check the glow plugs for continuity.
If a problem is found, repair as necessary.
Was a problem found?
—Verify repair Go to Step 17
17 Remove the CKP sensor from the flywheel housing
and check for the following conditions.
Objects sticking the CKP sensor.
Objects sticking the CKP sensor pulser.
If a problem is found, repair as necessary.
Was the problem found? —Verify repair Go to Step 18
18 Check the CKP sensor harness for the following
conditions.
Check for poor connector connection.
Check for misrouted harness.
Check for any accessory parts which may cause
electric interference.
If a problem is found, repair as necessary.
Was a problem found? —Verify repair Go to Step 19 Step Action Value(s) Yes No

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–409
19 Substitute a known good CKP sensor and recheck.
Was the problem solved?—Go to Step 20Go to Step 21
20 Replace the CKP sensor.
Is the action complete?—Veri fy repai r—
21 1. Using the Tech 2 and ignition “On” and engine
“Run”.
2. Monitor the following parameters in the data
display.
“Desired Injection Quantity” & “Injection Quantity”
“Desired Injection Start” & “Actual Injection Start”
Are the large gap or unstable parameter displayed
between “Desired” and “Actual”?
—Go to Step 23Go to Step 22
22 Check the ex haust system for a possible restriction.
Damaged or collapsed pipes or catalytic converter.
Internal muffler failure.
If a problem is found, repair as necessary.
Was a problem found?—Verify repair Go to Step 23
23 Visually/physically inspect for the following conditions.
Restrict fuel supply system. Check for a pinched
fuel hose/pipe.
Check for a condition that causes fuel wax ing or
icing, such as the customer is using an incorrect
fuel type in winter season or water mix ed with the
fuel.
If a problem is found, repair as necessary.
Was a problem found?—Verify repair Go to Step 24
24 Replace the fuel filter.
Was the problem solved?—Verify repair Go to Step 25 Step Action Value(s) Yes No
When idling or part-throttle When accelerated


HighDesi red
Low
Ti m e Actu al
High
LowDe si red
Actu al
Time

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

6E–414 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
10 Remove the MAF & IAT sensor assembly and check
for the following conditions.
Objects blocking at the MAF sensor element.
If a problem is found, repair as necessary.
Was the problem found?—Verify repair Go to Step 11
11 Check the MAF sensor harness for the following
conditions.
Check for poor connector connection.
Check for misrouted harness.
Check for any accessory parts which may cause
electric interference.
If a problem is found, repair as necessary.
Was a problem found? —Verify repair Go to Step 12
12 Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?—Go to Step 13Go to Step 21
13 Replace the MAF & IAT sensor assembly.
Is the action complete?—Veri fy repai r—
14 1. Using the Tech 2 and ignition “On” and engine
“Run”.
2. Monitor the following parameters in the data
display.
“Desired Injection Quantity” & “Injection Quantity”
“Desired Injection Start” & “Actual Injection Start”
Are the large gap or unstable parameter displayed
between “Desired” and “Actual”?
—Go to Step 20Go to Step 15 Step Action Value(s) Yes No
When idling or part-throttle When accelerated


HighD esired
Low
Ti m e Actu al
High
LowD esired
Actual
Tim e

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–415
15 Using the Tech 2 or the vacuum pump and check the
EGR valve operation for the following condition
through the small window.
ÅERestrict shaft movement. Check for objects sticking
the shaft, broken diaphragm or ex cessive carbon
deposit.
Tech 2:
1. Using the Tech 2, ignition "On" and engine "On".
2. Select the "Miscellaneous Test" and perform the
"EGR Solenoid Test" in the "Solenoid".
3. Operate the Tech 2 in accordance with procedure.
Solenoid 95%: EGR Valve Open
Solenoid 5%: EGR Valve Close
Vacuum Pump:
1. Using the vacuum pump. Disconnect the original
vacuum hose and connect the hose to the EGR
valve.
2. Apply vacuum pressure.
Vacuum Apply: EGR Valve Open
Vacuum Release: EGR Valve Close
If a problem is found, repair as necessary.
Was the problem found?—Verify repair Go to Step 16
16 Check the ex haust system for a possible restriction.
Damaged or collapsed pipes or catalytic converter.
Internal muffler failure.
If a problem is found, repair as necessary.
Was a problem found?—Verify repair Go to Step 17 Step Action Value(s) Yes No

Vacuum Pump Small Window

ENGINE MECHANICAL (6VE1 3.5L) 6A-1
ENGINE
CONTENTS
Engine Mechanical.................................................6A
Engine Cooling........................................................6B
Engine Fuel.............................................................6C
Engine Electrical.....................................................6D1
Ignition System.......................................................6D2
Starting and Changing System.............................6D3 Driveability and Emissions.....................................6E
Engine Exhaust.......................................................6F
Engine Lubrication..................................................6G
Engine Speed Control System..............................6H
Induction...................................................................6J


ENGINE MECHANICAL (6VE1 3.5L)
CONTENTS

Service Precaution................................................. 6A-2
General Description............................................... 6A-3
Engine Diagnosis.................................................... 6A-4
Cylinder Head Cover LH........................................ 6A-21
Removal............................................................... 6A-21
Installation............................................................ 6A-21
Cylinder Head Cover RH....................................... 6A-23
Removal............................................................... 6A-23
Installation............................................................ 6A-23
Common Chamber................................................. 6A-24
Removal............................................................... 6A-24
Installation............................................................ 6A-25
Exhaust Manifold LH.............................................. 6A-26
Removal............................................................... 6A-26
Installation............................................................ 6A-26
Exhaust Manifold RH............................................. 6A-27
Removal............................................................... 6A-27
Installation............................................................ 6A-27
Crankshaft Pulley................................................... 6A-28
Removal............................................................... 6A-28
Installation............................................................ 6A-28
Timing Belt.............................................................. 6A-29
Removal............................................................... 6A-29
Installation............................................................ 6A-30
Camshaft................................................................. 6A-34
Removal............................................................... 6A-34
Installation............................................................ 6A-34
Cylinder Head......................................................... 6A-37
Removal............................................................... 6A-37
Installation............................................................ 6A-37
Valve Stem Oil Controller , Valve Spring
and Valve Guide.................................................... 6A-39
Removal................................................................ 6A-39
Installation............................................................. 6A-39
Piston, Piston Ring and Connecting Rod............ 6A-40
Removal................................................................ 6A-40
Installation............................................................. 6A-41
Crankshaft and Main Bearings.............................. 6A-43
Removal................................................................ 6A-43
Installation............................................................. 6A-44
Rear Oil Seal........................................................... 6A-48
Removal................................................................ 6A-48
Installation............................................................. 6A-48
Engine Assembly.................................................... 6A-49
Removal................................................................ 6A-49
Installation............................................................. 6A-49
Cylinder Head.......................................................... 6A-52
Cylinder Head and Associated Parts................ 6A-52
Disassembly......................................................... 6A-53
Clean..................................................................... 6A-53
Inspection and Repair......................................... 6A-53
Reassembly.......................................................... 6A-54
Valve Spring, Oil Controller, Valve, Valve
Guide....................................................................... 6A-56
Valve Spring, Oil Controller, Valve, Valve
Guide and Associated Parts............................. 6A-56
Disassembly......................................................... 6A-57
Inspection and Repair......................................... 6A-57
Reassembly.......................................................... 6A-61
Camshaft.................................................................. 6A-64
Camshaft and Associated Parts........................ 6A-64
Disassembly......................................................... 6A-64
Inspection and Repair......................................... 6A-65
Reassembly.......................................................... 6A-67