2007 ISUZU KB P190 engine coolant

6E–256 ENGINE DRIVEABILITY AND EMISSIONS
POOR FUEL ECONOMY SYMPTOM
DEFINITIONS: Fuel economy, as measured by an actual road test, is noticeably lower than expected. Also, economy
is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
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 visual/physical check performed? —Go to Step 4Go to Visual /
physical Check.
4 Check owner’s driving habits. • Is the A/C On full time (defroster mode On)?
• Are tires at the correct pressure?
• Are excessively heavy loads being carried?
• Is acceleration too much, too often? — Go to Step 5Go to Step 6
5 Review the items in Step 4 with the customer and advise as necessary.
Is the action complete? — System OK —
6 Visually/physically check: Vacuum hoses for splits, kinks, and improper connections and routing as
shown on the “Emission Control System Schematics”.
Was a problem found? — Verify repair Go to Step 7
7 Check for low engine coolant level. Was a problem found? — Verify repair Go to Step 8
8 Check for incorrect or faulty engine thermostat. Refer to Engine Cooling .
Was a problem found? — Verify repair Go to Step 9
9 Remove and check the air filter element for dirt or for restrictions.
Was a problem found? — Verify repair Go to Step 10
10 1. Using a Tech 2, display the MAP sensor value in comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed MAP sensor.
Was the problem found? — Verify repair Go to Step 11
11 1. Using a Tech 2, display the ECT sensor and IAT sensor value and warm up condition compared
with the typical data.
2. Check the specified value or wire.
Was the problem found? — Verify repair Go to Step 12
12 Check the knock sensor wire, shield wire, or installation condition.
Was a problem found? — Verify repair Go to Step 13
13 Check the fuel pressure. Refer to 6E-108 page “Fuel
System Diagnosis
” .
Was a problem found? — Verify repair Go to Step 14

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–265
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.
INTAKE AIR TEMPERATURE (IAT) SENSOR
Location
Installed to the intake duct housing.
Removal Procedure 1. Disconnect the negative battery cable.
2. Disconnect a IAT sensor connector from the IAT sensor.
3. Remove the IAT sensor from the intake duct.
Installation Procedure 1. Install the IAT sensor into intake air duct.
2. Connect a IAT sensor connector to the IAT sensor.
3. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–2

Visual / Physical Inspection ................................................................................................................................ 28
Intermittent ........................................................................................................................................................... 28
2.3 Engine Misfire without Internal Engine Noises .................................................................................. ............... 29
2.4 Engine Misfire with Abnormal Internal Lower Engine Noises...................................................................... .... 30
2.5 Engine Misfire with Abnormal Valve Train Noise .............................................................................................. 31
2.6 Engine Misfire with Coolant Consumption ........................................................................................................ 31
2.7 Engine Misfire with Excessive Oil Consumption .................................................................................. ............ 31
2.8 Engine Noise on Start-up, but only Lasting a Few Seconds ....................................................................... ..... 31
2.9 Upper Engine Noise, Regardless of Engine Speed........................................................................................... 33
2.10 Lower Engine Noise, Regardless of Engine Speed ................................................................................. ......... 34
2.11 Engine Noise Under Load ................................................................................................................................... 35
2.12 Engine Will Not Crank – Crankshaft Will Not Rotate ............................................................................. ........... 35
2.13 Coolant in Combustion Chamber ....................................................................................................................... 37
Definition .............................................................................................................................................................. 37
2.14 Coolant in Engine Oil.......................................................................................................... ................................. 37
Definition .............................................................................................................................................................. 37
2.15 Engine Compression Test ........................................................................................................ ........................... 38
Preliminary Steps................................................................................................................................................. 38
Engine Cylinder Compression Test ............................................................................................... .................... 38
Test Result Evaluation......................................................................................................................................... 38
2.16 Cylinder Leakage Test .......................................................................................................... ............................... 39
2.17 Engine Oil Consumption Diagnosis ............................................................................................... .................... 39
Definition .............................................................................................................................................................. 39
2.18 Engine Oil Leak Diagnosis ...................................................................................................... ............................ 40
Introduction .......................................................................................................................................................... 40
Locating and Identifying the Leak .............................................................................................. ........................ 40
Visual Inspection ................................................................................................................................................. 40
Powder Method .................................................................................................................. .................................. 40
Black Light and Dye Method ..................................................................................................... .......................... 40
Possible Causes for Engine Oil Leaks ........................................................................................... .................... 41
2.19 Engine Oil Pressure Diagnosis ........................................................................................................................... 42
2.20 Accessory Drive Belt Diagnosis ................................................................................................. ........................ 42
Tension Check ..................................................................................................................................................... 42
Inspect .................................................................................................................................................................. 42
Drive Belt Chirp .................................................................................................................................................... 43
Definition .......................................................................................................................................................... 43
Diagnostic Aids................................................................................................................................................. 43
Test Description ............................................................................................................... ................................ 43
Diagnostic Table............................................................................................................................................... 44
Drive Belt Squeal .............................................................................................................. ................................... 45
Definition .......................................................................................................................................................... 45
Diagnostic Aids................................................................................................................................................. 45
Test Description ............................................................................................................... ................................ 45
Diagnostic Table............................................................................................................................................... 46
Drive Belt Whine ............................................................................................................... ................................... 46
Definition .......................................................................................................................................................... 46
Diagnostic Aids................................................................................................................................................. 46
Test Description ............................................................................................................... ................................ 46
Diagnostic Table............................................................................................................................................... 47
Drive Belt Rumble .............................................................................................................. .................................. 47
Definition .......................................................................................................................................................... 47
Diagnostic Aids................................................................................................................................................. 48
Test Description ............................................................................................................... ................................ 48
Diagnostic Table............................................................................................................................................... 48
Drive Belt Vibration........................................................................................................... ................................... 49
Definition .......................................................................................................................................................... 49
Diagnostic Aids................................................................................................................................................. 49
Test Description ............................................................................................................... ................................ 49
Diagnostic Table............................................................................................................................................... 50
Drive Belt Falls Off ........................................................................................................... .................................... 50

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–9

• Faulty operation or performance of any systems or components which depend on the proper operation or
performance of the system or component under repair,
• Damage to fasteners, basic tools or special tools and / or
• Leakage of coolant, lubricant or other vital fluids.
NOTE defined
A NOTE statement immediately precedes or follows an operating procedure, maintenance practice or condition that
requires highlighting. A NOTE statement also emphasises necessary characteristics of a diagnostic or repair procedure.
A NOTE statement is designed to:
• Clarify a procedure,
• Present additional information for accomplishing a procedure,
• Give insight into the reasons for performing a procedure in the recommended manner, and / or
Present information that gives the technician the benefit of past experience in accomplishing a procedure with greater
ease.

1.2 Engine Components
Major Component Assemblies


BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–12

Engine Front Cover

Figure 6A1 – 4
Legend
1 Engine Front Cover Locating Pin
2 Engine Front Cover Bolt, M10
3 Engine Front Cover
4 Engine Front Cover Gasket
5 Engine Front Cover Bolt, M8
6 Engine Front Cover Seal
7 Coolant Pump Assembly
8 Coolant Pump Bolt
9 Coolant Pump Gasket 10 Coolant Pump Pulley
11 Coolant Pump Pulley Bolt
12 Crankshaft Balancer
13 Crankshaft Balancer Bolt
14 Camshaft Position Sensor
15 Camshaft Position Sensor O-ring
16 Camshaft Position Sensor Bolt
17 Camshaft Position Actuator Solenoid Valve Seal


BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–15

Cylinder Head Assembly

Figure 6A1 – 7
Legend
1 Cylinder Head, Left-hand
2 Cylinder Head, Right-hand
3 Cylinder Head Gasket, Left-hand
4 Cylinder Head Gasket, Right-hand
5 Cylinder Head Bolt
6 Cylinder Head Front Bolt
7 Cylinder Head Coolant Hole Threaded Plug
8 Spark Plug Sleeve
9 Cylinder Head Oil Gallery Expansion Plug
10 Exhaust Valve
11 Intake Valve
12 Valve Rocker Arm Assembly
13 Hydraulic Valve Lash Adjuster Assembly
14 Valve Stem Oil Seal 15 Valve Spring
16 Valve Spring Cap
17 Valve Stem Key
18 Cylinder Head Camshaft Front Thrust Bearing Cap
19 Camshaft Oil Seal Ring
20 Exhaust Camshaft
21 Intake Camshaft, Left-hand (bank 2)
22 Intake Camshaft, Right-hand (bank 1)
23 Exhaust Camshaft, Right-hand (bank 1)
24 Cylinder Head Camshaft Cap – Intermediate
25 Cylinder Head Camshaft Cap Bolt
26 Cylinder Head Oil Galley Check Valve
27 Engine Coolant Temperature Sensor

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–17

Engine Block Assembly

Figure 6A1 – 9
Legend
1 Piston and Connecting Rod Assembly
2 Crankshaft Bearing Cap
3 Crankshaft Bearing Thrust Cap
4 Crankshaft Bearing Cap Inboard Bolt
5 Crankshaft Bearing Cap Outboard Bolt
6 Crankshaft Bearing Cap Side Bolt, Short
7 Crankshaft Bearing Cap Side Bolt, Long
8 Engine Block Oil Gallery Expansion Plug, 10 mm
9 Crankshaft
10 Crankshaft Sprocket Locating Pin
11 Crankshaft Upper Bearing
12 Crankshaft Lower Bearing
13 Crankshaft Upper Thrust Bearing #3 14 Engine Block Oil Gallery Expansion Plug, 14 mm
15 Engine Block Oil Gallery Threaded Plug, 14 mm
16 Engine Block Coolant Drain Threaded Plug, 14 mm
17 Engine Block Oil Gallery Threaded Plug, 20 mm
18 Engine Block Core Coolant Expansion Plug, 34.3 mm
19 Transaxle Locating Pin
20 Crankshaft Rear Oil Seal Housing Assembly
21 Crankshaft Rear Oil Seal Housing Assembly Bolt
22 Oil Pan Locating Pin
23 Cylinder Head Locating Pin
24 Piston Oil Nozzle
25 Piston Oil Nozzle Bolt

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–30

Cause Correction
Faulty cylinder head gasket and/or cracking or other
damage to the cylinder head and cylinder block coolant
passages.
Coolant consumption may or may not cause the engine to
overheat. 1 Inspect the spark plugs for coolant saturation, refer to
6C1-3 Engine Management – V6 – Service
Operations.
2 Inspect the cylinder heads, cylinder block and/or head gaskets, refer to 3.22 Cylinder Head Assembly and/or
4.7 Cylinder Block.
3 Repair or replace components as required.
W orn piston rings.
Oil consumption may or may not cause the engine to
misfire. 1 Inspect the spark plugs for oil deposits, refer to 6C1-3
Engine Management – V6 – Service Operations.
2 Check the cylinders for a loss of compression, refer to 2.15 Engine Compression Test.
3 Perform compression testing to identify the cause of low compression.
4 Repair or replace components as required.
A damaged crankshaft reluctor wheel.
A damaged crankshaft reluctor wheel can result in different
symptoms depending on the severity and location of the
damage.
Systems with severe reluctor ring damage may exhibit
periodic loss of crankshaft position, stop delivering a signal,
and then re-sync the crankshaft position.
Systems with slight reluctor ring damage may exhibit no
loss of crankshaft position and no misfire may occur,
however, a DTC may set. Replace the crankshaft as required, refer to 4.6
Crankshaft and Main Bearings.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs
2.4 Engine Misfire with Abnormal Internal Lower Engine Noises
Cause Correction
Abnormalities, severe cracking, bumps or missing areas in
the accessory drive belt.
Abnormalities in the accessory drive system and/or
components may cause engine speed variations that result
in a misfire diagnostic trouble code (DTC). A misfire code
may be present without an actual misfire condition. Replace the accessory drive belt, refer to 3.5
Accessory
Drive Belt.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs
W orn, damaged or misaligned accessory drive components
and excessive pulley run-out may lead to a misfire DTC.
A misfire code may be present without an actual misfire
condition. Inspect the components and repair or replace as required.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs
Loose or Incorrectly fitted flexplate or crankshaft balancer
assembly.
A misfire code may be present without an actual misfire
condition. Repair or replace the flexplate or crankshaft balancer as
required, refer to 3.13 Crankshaft Balancer Assembly
or 4.3 Flexplate Assembly.
W orn or broken piston rings.
Oil consumption may or may not cause an actual misfire. 1 Inspect the spark plugs for oil deposits, refer to 6C1-3
Engine Management – V6 – Service Operations.
2 Check the cylinders for a loss of compression, refer to 2.15 Engine Compression Test.
3 Perform compression testing to identify the cause of low compression.
4 Repair or replace components as required.
W orn crankshaft thrust bearing.
Severely worn thrust surfaces on the crankshaft and/or
thrust bearing may permit fore and aft movement of the
crankshaft and create a DTC without an actual misfire
condition being present. Replace the crankshaft and/or bearings as required, refer to
4.6 Crankshaft and Main Bearings.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007