service indicator ISUZU KB P190 2007 Workshop Owner's Manual

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-355
Electrostatic Discharge Damage
Electronic components used in the ECM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. By comparison, as much as
4,000 volts may be needed for a person to feel even
the zap of a static discharge. There are several ways
for a person to become statically charged. The most
common methods of charging are by friction and
induction.
• An example of charging by friction is a person sliding across a vehicle seat.
Important: To prevent possible electrostatic discharge
damage, follow these guidelines:
• Do not touch the ECM connector pins or soldered components on the ECM circuit board.
• Do not open the replacement part package until the part is ready to be installed.
• Before removing the part from the package, ground the package to a known good ground on
the vehicle.
• If the part has been handled while sliding across the seat, while sitting down from a standing
position, or while walking a distance, touch a
known good ground before installing the part.
• Charge by induction occurs when a person with well insulated shoes stands near a highly charged
object and momentarily touches ground. Charges
of the same polarity are drained off leaving the
person highly charged with opposite polarity.
Malfunction Indicator Lamp (MIL) Operation
The MIL is located in the instrument panel cluster. The
MIL will display the following symbols when
commanded ON: The MIL indicates that an emission related fault (Type
A or B) has occurred (Euro 4 specification) or engine
performance related fault has occurred (except Euro 4
specification) and vehicle service is required. The
following is a list of the modes of operation for the MIL:
• The MIL illuminates when the ignition switch is turned ON, with the engine OFF. This is a bulb test
to ensure the MIL is able to illuminate.
• The MIL turns OFF after the engine is started if a diagnostic fault is not present.
• The MIL remains illuminated after the engine is started if the ECM detects a fault. A DTC is stored
any time the ECM illuminates the MIL due to an
emission related fault (Euro 4 specification), and
engine performance related fault has occurred
(except Euro 4 specification).
Service Vehicle Soon (SVS) Lamp Operation (Euro
4 Specification)
The service vehicle soon (SVS) lamp is located in the
instrument panel cluster. The SVS lamp will display the
following symbol when commanded ON:
The SVS lamp indicates that a non-emission related
fault (Type C) has occurred and vehicle service
required. The following is a list of the modes of
operation for the SVS lamp:
• The SVS lamp illuminates when the ignition switch is turned ON, with the engine OFF. This is a bulb
test to ensure the SVS lamp is able to illuminate.
• The SVS lamp turns OFF after the engine is started if a diagnostic fault is not present.
• The SVS lamp remains illuminated after the engine is started if the ECM detects a fault. A DTC is
stored any time the ECM illuminates the SVS lamp
due to a non-emission related fault.
RTW76ESH001901
RTW76ESH002901

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–232 ENGINE DRIVEABILITY AND EMISSIONS
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 malfunction indicator lamp (MIL = Check Engine 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, shown on the “Emission Control System
Schematics”. 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 malfunction indicator lamp (MIL) or store a
Diagnostic Trouble Code. Do NOT use the Diagnostic
Trouble Code (DTC) charts for 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. • MIL (Check Engine Lamp) wire to ECM shorted to
ground.
• Poor ECM grounds. Refer to the ECM wiring diagrams.
Road test the vehicle with a Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 has several features that can be used to located
an intermittent condition.
An intermittent MIL (Check Engine 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.
• MIL (Check Engine 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 compressor
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).
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 “XBYA”
(example only).
This identifies the contents of the reprogrammable
software and calibration contained in the ECM.
If the “Broadcast Code” is not the most current
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 allow
incorrect software programming or incorrect calibration
changes.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–3

Definition .......................................................................................................................................................... 50
Diagnostic Aids................................................................................................................................................. 50
Test Description ............................................................................................................... ................................ 50
Diagnostic Table............................................................................................................................................... 51
Drive Belt Excessive Wear ...................................................................................................... ............................ 51
Definition .......................................................................................................................................................... 51
Diagnostic Aids................................................................................................................................................. 52
Test Description ............................................................................................................... ................................ 52
Diagnostic Table............................................................................................................................................... 52
Accessory Drive Belt Tensioner Diagnosis ....................................................................................... ................ 52
Diagnostic Table............................................................................................................................................... 52
3 Minor Service Operations ....................................................................................................... .............53
3.1 Engine Oil ............................................................................................................................................................. 54
Check .................................................................................................................................................................... 54
Replace ........................................................................................................................ ......................................... 54
Pressure Check ................................................................................................................. ................................... 55
3.2 Oil Filter Cartridge ............................................................................................................................................... 56
Replace ................................................................................................................................................................. 56
3.3 Oil Filter Adaptor............................................................................................................. ..................................... 57
Remove ................................................................................................................................................................. 57
Reinstall ................................................................................................................................................................ 57
3.4 Oil Level Indicator Tube ....................................................................................................... ............................... 58
Remove ............................................................................................................................................................ 58
Reinstall ........................................................................................................................................................... 58
3.5 Accessory Drive Belt ........................................................................................................... ................................ 59
RWD Vehicle ......................................................................................................................................................... 59
Remove ............................................................................................................................................................ 59
Reinstall ........................................................................................................................................................... 59
3.6 Accessory Drive Belt Idler Pulley .............................................................................................. ......................... 60
Remove ............................................................................................................................................................ 60
Reinstall ........................................................................................................................................................... 60
3.7 Accessory Drive Belt Tensioner Assembly ........................................................................................ ............... 61
Remove ............................................................................................................................................................ 61
Reinstall ........................................................................................................................................................... 61
3.8 Power Steering Pump Bracket .................................................................................................... ........................ 62
Remove ................................................................................................................................................................. 62
Reinstall ................................................................................................................................................................ 62
3.9 Upper Intake Manifold.......................................................................................................... ................................ 62
Remove ................................................................................................................................................................. 63
Disassemble ......................................................................................................................................................... 66
Clean ..................................................................................................................................................................... 66
Inspect .................................................................................................................................................................. 66
Reassemble .......................................................................................................................................................... 67
Reinstall ...................................................................................................................... .......................................... 67
3.10 Intake Manifold Assembly – Complete............................................................................................ ................... 68
Remove ................................................................................................................................................................. 68
Disassemble ......................................................................................................................................................... 72
Clean ..................................................................................................................................................................... 73
Inspect .................................................................................................................................................................. 73
Reassemble .......................................................................................................................................................... 74
Reinstall ...................................................................................................................... .......................................... 74
3.11 Exhaust Manifold Assembly ...................................................................................................... ......................... 75
Remove ................................................................................................................................................................. 75
Inspect .................................................................................................................................................................. 77
Reinstall ................................................................................................................................................................ 77
3.12 Camshaft Cover ................................................................................................................. .................................. 79
Remove ................................................................................................................................................................. 79
Clean and Inspect .............................................................................................................. .................................. 81

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–39

2.16 Cylinder Leakage Test
A leakage test may be performed to measure cylinder/combustion chamber leakage. High cylinder leakage may indicate
one or more of the following:
• worn or burnt valves,
• broken valve springs,
• stuck valve lifters,
• incorrect valve lash/adjustment,
• damaged piston,
• worn piston rings,
• worn or scored cylinder bore,
• damaged cylinder head gasket,
• cracked or damaged cylinder head, or
• cracked or damaged engine block.

1 Disconnect the battery ground negative cable.
2 Remove the spark plugs from all cylinders, refer to 6C1-3 Engine Management – V6 – Service Operations.
3 Rotate the crankshaft to place the piston in the cylinder being tested at top dead centre (TDC) of the compression stroke.
4 Install a commercially available cylinder head leak down tester into the spark plug hole.
NOTE
If required, hold the crankshaft balancer bolt to
prevent the engine from rotating.
5 Apply shop air pressure to the cylinder head leak down tester and adjust according to the manufacturers instructions.
6 Record the cylinder leakage value. Cylinder leakage that exceeds 25 percent is considered excessive and may require component service. In excessive leakage situations, inspect for the following conditions:
• air leakage sounds at the throttle body or air inlet duct that may indicate a worn or burnt intake valve or a
broken valve spring,
• air leakage sounds at the exhaust system tailpipe that may indicate a worn or burnt exhaust valve or a broken
valve spring,
• air leakage sounds from the crankcase, oil level indicator tube, or oil fill tube that may indicate worn piston
rings, a damaged piston, a worn or scored cylinder bore, a damaged engine block or a damaged cylinder
head, or
• air bubbles in the cooling system may indicate a damaged cylinder head or a damaged cylinder head gasket.
7 Perform the leakage test on the remaining cylinders and record the values.
2.17 Engine Oil Consumption Diagnosis
Definition
Excessive oil consumption (not due to leaks) is the use of 3 litres or more of engine oil within 10,000 kilometres. Prior to
performing oil pressure testing, a preliminary inspection of the vehicle should be performed. During the preliminary visual
inspection, the following likely causes of excessive oil usage should be investigated.
Cause Correction
External oil leaks. Refer to 2.18 Engine Oil Leak Diagnosis.
Incorrect oil level or reading of the oil level indicator. Check for the correct oil level, refer to 3.1 Engine Oil.
Incorrect oil viscosity. Replace the engine oil, using the recommended SAE grade
of engine oil, refer to 3.1 Engine Oil.
Continuous high-speed driving or severe usage. Service vehicle more frequently, refer to 0B Lubrication and
Service.
Crankcase ventilation system restricted or malfunctioning. Repair or replace crankcase ventilation system components as required, refer to 6C1-3 Engine Management – V6 –
Service Operations.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–169

Valve Guide Measurement
1 Measure the valve stem (1) to-guide (2) clearance.
Excessive valve stem-to-guide clearance may cause
excessive oil consumption and may also cause a
valve to break. Insufficient clearance will result in
noisy and sticky functioning of the valve and will
disturb the engine assembly smoothness.
2 Clamp a dial indicator to the cylinder head at the camshaft cover rail.
3 Locate the dial indicator so the movement of the valve stem from side to side, crossways to the cylinder
head, will cause a direct movement of the indicator
stem. The dial indicator stem must contact the side of
the valve stem just above the valve guide.
4 Drop the valve head about 0.064 mm off the valve seat.
5 Use light pressure when moving the valve stem from side to side to obtain a clearance reading, refer to 5
Specifications.
• If the clearance for the valve is greater than
specified and a new standard diameter valve
stem will not bring the clearance within
specifications, the valve guide may be oversized
by 0.075 mm using the valve guide reamer, Tool
No. J 42096 or by 0.375 mm using the valve
guide reamer, Tool No. EN-46120. Two sizes of
oversized valve stems are available for service.
• Valve guide wear at the bottom 10 mm of the
valve guide is not significant enough to affect
normal operation.
• If over sizing the guide does not bring the
clearance within specifications, replace the
cylinder head.
Figure 6A1 – 289
Valve Spring Inspection and Measurement
Inspection Procedure
1 Clean the valve springs in solvent.

Safety glasses must be worn when using
compressed air
2 Dry the valve springs with compressed air.
3 Inspect the valve springs for broken coils or coil ends.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–198

k Timing chains, tensioners, shoes, guides & sprockets, refer to 3.16 Timing Chains, Tensioners, Shoes and
Guides.
l Cylinder head assemblies, refer to 3.22 Cylinder Head Assembly.
m Oil pan assembly, refer to 4.2 Oil Pan and Oil Pump Suction Pipe Assembly.
n Piston and connecting rod assemblies, refer to 4.5 Pistons, Pins, Rings, Connecting Rods and Big-end Bearings.
o Crankshaft assembly, refer to 4.6 Crankshaft and Main Bearings.
p Piston oil nozzles, refer 4.5 Pistons, Pins, Rings, Connecting Rods and Big-end Bearings.
Reassemble
Reassembly of the engine assembly is the reverse of the disassembly procedure.
Reinstall
Reinstallation of the engine assembly is the reverse to the removal procedure, noting the following:
NOTE
Refer to 6 Torque Wrench Specifications
for the correct torque specifications.


1 Tighten the fasteners to the correct torque specification.
Engine ground connector bolt
torque specification ............................................10.0 Nm
Power steering high pressure line
attaching bolt torque specification .............8.0 – 12.0 Nm
Power steering high pressure line
flare nut torque specification ...................25.0 – 35.0 Nm
Engine mount to frame attaching bolt
torque specification .................................44.0 – 60.0 Nm
Knock Sensor Attaching Nut
torque specification ............................................23.0 Nm
2 Use only the specified engine lubricant type and quantity. It is recommended that a fluorescent oil dye, such as that contained in J 28481-B, be added to assist in any future oil leak diagnosis.
3 Fill the cooling system with the correct quantity and grade of coolant, refer to 6B1 Engine Cooling – V6.
4 Check transmission fluid level, replenishing as required, using the specified lubricant for the transmission fitted, refer to 7C1 Automatic – 4L60E – General Information.
5 Disable the ignition system, refer to 6C1-3 Engine Management – V6 – Service Operations.
6 Crank the engine several times. Listen for any unusual noises or evidence that parts are binding.
7 Enable the ignition system. Start the engine and listen for any unusual noises.
8 Check the vehicle oil pressure gauge or warning indicator and confirm the engine has acceptable oil pressure. If required, install an oil pressure gauge and measure the engine oil pressure, refer to 2.19 Engine Oil Pressure
Diagnosis.
9 Run the engine at about 1,000 r.p.m. until the engine has reached normal operating temperature.
10 Listen for any unusual noises.
11 Check for oil, fuel, coolant and exhaust leaks while the engine is running, correcting as required.
12 Perform a final inspection for correct engine oil and coolant levels.

4.2 Oil Pan and Oil Pump Suction Pipe Assembly
Remove
1 Remove the engine assembly from the vehicle, refer to 4.1 Engine .
2 Separate the engine and transmission assemblies, refer to 7C1 Automatic – 4L60E – General Information.
3 Mount the engine assembly on a suitable engine stand.
4 Remove the engine front cover, refer to 3.15 Front Cover Assembly.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–223


NOTE
During and after installation, ensure each piston
is positioned correctly in the correct cylinder. The
locating arrow on the top of each piston must be
pointing toward the front of the engine.
6 Repeat these procedures for the remaining piston/connecting rod assemblies.
7 Reinstall the oil pan and oil pump pick up assembly, refer to 4.2 Oil Pan and Oil Pump Suction Pipe Assembly.
8 Reinstall the cylinder heads, refer to 3.22 Cylinder Head Assembly.
9 Reinstall the engine assembly, refer to 4.1 Engine .
4.6 Crankshaft and Main Bearings
1 Remove the engine assembly, refer to 4.1 Engine .
2 Remove both cylinder head assemblies, refer to 3.22 Cylinder Head Assembly.
3 Remove the oil pan assembly, refer to 4.2 Oil Pan and Oil Pump Suction Pipe Assembly.
4 Remove the piston and connecting rod assemblies, refer to 4.5 Pistons, Pins, Rings, Connecting Rods and Big- end Bearings.
5 Remove the oil pump assembly, refer to 3.17 Oil Pump Assembly.
6 Remove the crankshaft rear oil seal and plate assembly, refer to 4.4 Crankshaft Rear Seal and Plate Assembly.
7 Remove the crankshaft position sensor, refer to 6C1-3 Engine Management – V6 – Service Operations.
Crankshaft End Play Measurement
1 Place a dial indicator at the end of the crankshaft nose.
2 Gently force the crankshaft towards the front and rear of the cylinder block with a lever while monitoring the movement of the dial indicator.
3 The crankshaft endplay should not exceed specifications, refer to 5 Specifications.
4 If the specifications are exceeded, inspect the thrust bearing thrust outer diameter and the crankshaft thrust wall for wear and/or excessive runout. Compare the values with the specifications, refer to 5 Specifications.
5 Replace the thrust bearing or crankshaft as required.
Remove
1 Remove the crankshaft bearing cap side bolts (3).
CAUTION
The crankshaft bearing cap outer bolts are
yield tightened during assembly and must
be replaced prior to reassembly. Crankshaft
bearing cap outer bolts that are not replaced
will not torque to the correct clamp load and
can lead to serious engine damage.
2 Remove the crankshaft bearing cap outer bolts (1).
3 Remove the crankshaft bearing cap inner bolts (2).
Figure 6A1 – 410

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–229

3 Measure the crankshaft thrust wall width (1) for wear
using an inside micrometer and compare with the
engine specifications, refer to 5 Specifications.
4 Measure the crankshaft thrust wall surface (2) for runout using a dial indicator, mounted to a magnetic
stand and compare with the engine specifications,
refer to 5 Specifications.
5 If the crankshaft journals are damaged or worn beyond specifications, the crankshaft may be ground
0.25 mm. There is only one size of oversized main
bearings available for service.

Figure 6A1 – 422
6 Inspect the crankshaft main journals (1) for undersize, using an outside micrometer (2).

Figure 6A1 – 423
7 Inspect the crankpins (1) for undersize using an outside micrometer (2).
8 Compare your measurements with those listed in the engine specifications, refer to 5 Specifications.
If the crankpin journals are worn beyond the
specifications, the crankshaft may be ground 0.25
mm. Only one size of oversized connecting rod
bearings available for service.

Figure 6A1 – 424

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–3
Page 6A1–3
Definition ..................................................................................................................... .....................................62
Diagnostic Aids................................................................................................................................................. 62
Test Description ............................................................................................................... ................................62
Diagnostic Table............................................................................................................... ................................62
Drive Belt Excessive Wear ...................................................................................................... ............................64
Definition ..................................................................................................................... .....................................64
Diagnostic Aids................................................................................................................................................. 64
Test Description ............................................................................................................... ................................64
Diagnostic Table............................................................................................................... ................................64
Accessory Drive Belt Tensioner Diagnosis ....................................................................................... ................65
Diagnostic Table............................................................................................................... ................................65
3 Minor Service Operations ....................................................................................................... .............66
3.1 Engine Oil ..................................................................................................................... ........................................66
Check.................................................................................................................................................................... 66
Replace ........................................................................................................................ .........................................67
Pressure Check ................................................................................................................. ...................................68
3.2 Oil Filter Cartridge ........................................................................................................... ....................................69
Replace ........................................................................................................................ .........................................69
3.3 Oil Filter Adaptor............................................................................................................. .....................................70
Remove ................................................................................................................................................................. 70
Reinstall ................................................................................................................................................................ 70
3.4 Oil Level Indicator Tube ...................................................................................................................................... 71
Remove ................................................................................................................................................................. 71
Reinstall ................................................................................................................................................................ 71
3.5 Accessory Drive Belt ........................................................................................................................................... 72
RWD Vehicle ......................................................................................................................................................... 72
Remove ............................................................................................................................................................72
Reinstall ...................................................................................................................... .....................................73
3.6 Accessory Drive Belt Idler Pulley .............................................................................................. .........................74
Remove ................................................................................................................................................................. 74
Reinstall ................................................................................................................................................................ 74
3.7 Accessory Drive Belt Tensioner Assembly ........................................................................................ ...............75
Remove ................................................................................................................................................................. 75
Reinstall ................................................................................................................................................................ 75
3.8 Power Steering Pump Bracket .................................................................................................... ........................76
Remove ................................................................................................................................................................. 76
Reinstall ................................................................................................................................................................ 76
3.9 Upper Intake Manifold .......................................................................................................... ...............................77
Remove ................................................................................................................................................................. 77
Disassemble ......................................................................................................................................................... 80
Clean..................................................................................................................................................................... 80
Inspect ........................................................................................................................ ..........................................81
Reassemble .......................................................................................................................................................... 81
Reinstall ................................................................................................................................................................ 82
3.10 Intake Manifold Assembly – Complete............................................................................................ ...................83
Remove ................................................................................................................................................................. 83
Disassemble ......................................................................................................................................................... 87
Clean..................................................................................................................................................................... 88
Inspect ........................................................................................................................ ..........................................88
Reassemble .......................................................................................................................................................... 89
Reinstall ................................................................................................................................................................ 89
3.11 Exhaust Manifold Assembly ...................................................................................................... .........................91
Remove ................................................................................................................................................................. 91
Inspect ........................................................................................................................ ..........................................93
Reinstall ................................................................................................................................................................ 93
3.12 Camshaft Cover ................................................................................................................. ..................................94
Remove ................................................................................................................................................................. 94
Clean and Inspect .............................................................................................................. ..................................96

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–46
Page 6A1–46
2.16 Cylinder Leakage Test
A leakage test may be performed to measure cylinder/combustion chamber leakage. High cylinder leakage may indicate
one or more of the following:
• worn or burnt valves,
• broken valve springs,
• stuck valve lifters,
• incorrect valve lash/adjustment,
• damaged piston,
• worn piston rings,
• worn or scored cylinder bore,
• damaged cylinder head gasket,
• cracked or damaged cylinder head, or
• cracked or damaged engine block.

1 Disconnect the battery ground negative cable.
2 Remove the spark plugs from all cylinders, refer to Section 6C1-3 Engine Management – V6 – Service Operations.
3 Rotate the crankshaft to place the piston in the cyli nder being tested at top dead centre (TDC) of the compression
stroke.
4 Install a commercially available cylinder head leak down tester into the spark plug hole.
NOTE
If required, hold the crankshaft balancer bolt to
prevent the engine from rotating.
5 Apply shop air pressure to the cylinder head leak dow n tester and adjust according to the manufacturers
instructions.
6 Record the cylinder leakage value. Cylinder leakage t hat exceeds 25 percent is considered excessive and may
require component service. In excessive leakage situations, inspect for the following conditions:
• air leakage sounds at the throttle body or air inlet duct that may indicate a worn or burnt intake valve or a
broken valve spring,
• air leakage sounds at the exhaust system tailpipe that may indicate a worn or burnt exhaust valve or a broken
valve spring,
• air leakage sounds from the crankcase, oil level indicator tube, or oil fill tube that may indicate worn piston
rings, a damaged piston, a worn or scored cylinder bore, a damaged engine block or a damaged cylinder
head, or
• air bubbles in the cooling system may indicate a damaged cylinder head or a damaged cylinder head gasket.
7 Perform the leakage test on the rema ining cylinders and record the values.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007