Page 1786 of 4264

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
Page 1788 of 4264

6E–416 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
17 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 18
18 Check the engine compression pressure for each
cylinders.
If a problem is found, repair as necessary.
Was the problem found?
More than 20
Mpa Verify repair Go to Step 19
19 Check the inlet/ex haust valve clearance for each
valves.
Are the valve clearances within the specified value?
0.4mm at cold
(In/Ex ) Go to Step 20Adjust and
verify repair
20 1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
followi ng:
Visual/physical inspection
Tech 2 data
All electrical connections within a suspected circuit
and/or system
Was a problem found?—Verify repair Go to Step 21 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
Page 1790 of 4264

6E–418 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ON-VEHICLE SERVICE PROCEDURE
ENGINE CONTROL MODULE
(ECM)
Location
Under the left-hand side seat.
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the seat left-hand side.
3. Roll up the floor carpet.
4. Remove four bolts from the ECM cover.
5. Disconnect the two connectors from the ECM.
Installation Procedure
1. Connect the two connectors to the ECM.
2. Put on the ECM to the floor panel.
3. Tighten the ECM cover by four bolts with specifiedtightening torque.
Tightening torque
Bolts: 8.0 - 12.0 N·m (0.8 - 1.2 kgf·m)
4. Lay the floor carpet ex actly.
5. Put on the seat to the floor panel and tighten with
specified tightening torque.
Tightening torque
Bolts: 40.0 N·m (4.1 kgf·m)
6. Connect the negative battery cable.
NOTE: The replacement ECM must be programmed.
Refer to section of the Service Programming System
(SPS) in this manual.
Following ECM programming, the immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement” for the
ECM/Immobilizer linking procedure.
Page 1791 of 4264

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–419
CRANKSHAFT POSITION (CKP)
SENSOR
Location
Installed to the clutch housing.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect connector from the CKP sensor.
3. Loosen a bolt and remove the CKP sensor from the
clutch housing.
Installation Procedure
1. Install the CKP sensor to the clutch housing.
2. Tighten CKP sensor by a bolt with specified
tightening torque.
Tightening Torque
Bolts: 8.0 - 12.0 N·m (0.8 - 1.2 kgf·m)
3. Connect a CKP sensor connector to the CKP
sensor.
4. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
ENGINE COOLANT TEMPERATURE
(ECT) SENSOR
Location
Installed to the thermostat housing.
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain enough engine coolant so that the coolant
level will be below the ECT sensor.
3. Disconnect connector from the ECT sensor.
4. Loosen and remove the ECT sensor from the
thermostat housing.
NOTE: Cool down the engine before above procedures
are carried out.
Installation Procedure
1. Apply sealer to threads of screw at the ECT sensor.
2. Tighten the ECT sensor with specified tightening
torque.
Tightening Torque
Bolt: 13N·m (1.3kgf·m)
3. Connect a ECT sensor connector to the ECT
sensor.
4. Fill the engine coolant.
5. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Verify no engine coolant leaking from the sensor
threads after replacement.
Page 1792 of 4264

6E–420 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
MASS AIR FLOW (MAF) & INTAKE
AIR TEMPERATURE (IAT) SENSOR
Location
Installed to the intake duct housing.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect a MAF & IAT sensor connector from the
MAF & IAT sensor assembly.
3. Loosen the clips and remove the MAF & IAT sensor
assembly from the intake duct housing.
Installation Procedure
1. Install the MAF & IAT sensor assembly into intake
air duct.
2. Tighten the clips.
3. Connect a MAF & IAT sensor connector to the MAF
& IAT sensor assembly.
4. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
THROTTLE POSITION SENSOR
(TPS)
Location
Installed on the throttle body.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the TPS connector.
3. Loosen two screws and remove TPS from the
throttle body.
Installation Procedure
1. Temporary tighten the TPS by two screws.
2. Connect a TPS connectors to the TPS.
3. Connect the Tech2 to the vehicle.
4. Connect the negative battery cable.
5. Select “Data Display” with the Tech2.
6. Check the throttle position data and adjust the TPS
position.
7. Tighten two screws.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Page 1793 of 4264
4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–421
EGR EVRV (Electrical Vacuum
Regulating Valve)
Location
Back of the air cleaner case.
Removal Procedure
1. Disconenct the negative battery cable.
2. Disconnect a EVRV connector from the EVRV.
3. Disconnect two hoses from the EVRV.
4. Loosen two bolts and remove the EVRV from the
bracket.
Installation Procedure
1. Tighten the purge solenoid by tow bolts.
2. Connect a connector to the EVRV.
3. Connect two hoses to the EVRV.
4. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Verify proper connection of two hoses.
Page 1811 of 4264

EXHAUST SYSTEM 6F – 17
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part replacements if excessive wear or damage is discovered during
inspection.
Turbocharger pressure check
1. Remove the hose between the master gate and the
compressor outlet pipe.
2. Connect the pressure gauge. To compressor outlet
pipe.
3. Start the engine and gradually increase the engine
speed (the vehicle must be stationary with no load
applied to the engine).
4. Check to see that turbocharger pressure rises to
approximately 300 mmHg.
Pressure Gauge : 5-8840-0075-0
150RY00030
Waste gate operation check
1. Remove the hose between the waste gate and the
compressor outlet pipe.
2. Connect the pressure gauge. To waste gate actuator.
3. Check to see that the rod begins to move when a
pressure of approximately 665 mmHg is applied to the
waste gate.
Note:
Do not apply a pressure greater than 1 kg/cm
2 to the
wastegate during this check.
150RY00031
Unit Inspection (Remove Turbo. from engine)
Check to see the pressure required to move the control
rod 2 mm is within the limits shown below.
Kpa/mmHg
4JH1TC 134.8/1011
4JA1TC 147.7/1108
150RY00032
Contact the “ISUZU MOTORS LIMITED” Dealer service
department or “IHI SERVICE FACILITY” for major repairs
and maintenance.
Important wheel shaft end play and bearing clearance
standards and limits are included below for your reference.
Page 1820 of 4264

6H – 6 ACCELERATOR CONTROL
RTW46HMH000201
Removal
1. Disconnect the accelerator control cable from the
accelerator pedal and dash panel.
2. Remove the cable clips.
3. Remove the accelerator control cable from accelerator
control cable bracket.
1) Slide the lock in direction A
2) Rotate the ratchet ring in undirection an arrow 90.
4. Remove the accelerator control cable from the throttle.
Inspection
Check the following items and replace the control cable if
any abnormality is found.
The control cable should move smoothly.
The control cable should not be bent or kinked.
The control cable should not be damage or
corrosion.
Installation
1. Install the accelerator control cable to accelerator
control pedal dash panel.
2. Install the accelerator control cable to throttle.
Attach T-END and inner cable to throttle cam of
engine.
3. Install accelerator control cable to accelerator bracket.
1) Rotate the ratchet ring in direction an arrow 90
until both white marking are aligned.
2) Confirm marking of outer cap must be upper side.
3) Slider the lock in direction B.
4) Confirm ratchet ring is locked.
4. Install the cable clips to accelerator control cable.
NOTE:
Confirm that the throttle (engine side) is at full stroke
when the accelerator pedal is at full stroke.