2007 ISUZU KB P190 oil temperature

Engine Cooling – V6 Engine Page 6B1–59

General Core Repair
NOTE
The need for careful preparation of the surface in
the repair area cannot be over-emphasised. If the
leak area surface is not clean, the repair material
will not adhere to the surface.

Refer to ‘
‘‘
‘
Environmental Issues ’
’’
’
in 3.1
Service Notes, before draining the coolant.
1 Drain the coolant from the system. Refer to 3.3 Draining and Filling Cooling System in this Section.
2 Remove the radiator. Refer to 3.15 Radiator in this Section.
3 If necessary, carefully cut away fins to expose the damaged area.
NOTE
Do not cut away more than 25 mm total fin
material.
4 Clean away dirt etc. with water. Dry the affected area using hot air from a hair drier.

Do not apply flame to dry damaged area.
5 Clean affected area with petrol to remove any traces of oil.
6 Thoroughly stir contents of repair agent.
NOTE
In cases of extended shelf life, the silicon in
solution may separate from the thinner base.
Should this occur, mix contents well until agent is
again homogeneous.
7 Apply repair agent sparingly to damaged area. Do not apply an excessive amount, as this will cause blockage of the radiator tube.
NOTE
Use a clean, dry wooden applicator to 'DRIP'
agent onto damaged area of radiator.
8 Allow radiator to stand in a clean, dry area for a minimum of 3 hours (at ambient temperature of 20 – 30 ° C) with
adequate ventilation.
NOTE
Do not apply heat or flame to promote drying.
9 Reinstall the radiator. Refer to 3.15 Radiator in this Section.

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Engine Cooling – V6 Engine Page 6B1–61

4 Engine Cooling System
Diagnosis
4.1 Poor Heater Operation
Little or no heat coming from the heater, especially at idle could be an indication of a cooling system problem.
As the coolant level begins to get lower than normal, air enters the system to replace the missing coolant. The heater
core is one of the highest parts of the cooling system and therefore, the first area to lose coolant circulation.
At first, with a small amount of coolant loss, lack of heat will be most noticeable at idle. As driving speed increases, the
engine pumps more coolant and more heat is now able to pass through the heater core.
If coolant level drops even lower, heater operation will become less effective, even during normal driving. Cooling and
engine systems can be adversely affected if problem is not corrected before overheating occurs.
4.2 Leaking Cylinder Head Gasket
Combustion gases leaking past the cylinder head gasket can pressurise the cooling system, forcing coolant out of the
system and into the coolant recovery reservoir.
Indications are air bubbles in the coolant or an overflow condition of the recovery reservoir.
4.3 Question the Customer
To avoid needless time and cost in diagnosing cooling system complaints, the customer should be questioned about
driving conditions that place abnormal loads on the cooling system.
1 Is overheating occurring after prolonged idle, in gear, with air conditioning system operating?
If answer is YES – instruct owner on driving techniques that would avoid overheating such as:
• Idle in neutral as much as possible – increase engine rpm to get higher air flow (due to an increase in voltage
to the fan) and coolant flow through the radiator
• Turn air conditioning system off during extended idling periods if overheating is indicated on temperature
gauge. Further diagnostic checks should not be required
2 Is overheating occurring after prolonged driving in slow city traffic, traffic jams, parades, etc?
If answer is YES, explain driving technique to the customer, that would avoid overheating – same as for prolonged idle – No.1. Further diagnostic checks should not be required.
4.4 Diagnostic Chart
If none of the above conditions apply, refer to the following Diagnosis Chart.
To effectively use this chart, question the customer to determine which of the following three categories apply to the
complaint:
1 If complaint is hot indication on temperature gauge.
W as temperature reading accompanied by boiling?
• If answer is YES, go to overheating on diagnosis chart
• If answer is NO, check temperature gauge and sender
2 If complaint is boiling – go to overheating on diagnosis chart.
3 If complaint is coolant loss. Determine if customer is filling the system correctly.
4 If incorrect filling is not the problem, go to coolant loss in the diagnosis chart.

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Engine Cooling – V6 Engine Page 6B1–62


Refer to 3.1 Service Notes in this Section, for
important safety items before removing the
coolant filler pressure cap or servicing the
system.

The cooling system is designed to operate at
120 –
––
–
130 kPa and a maximum temperature
not above 130 °
°°
°
C.
Cooling System Diagnosis
Step Action Result Yes No
1
Check Temperature gauge reading High Temp.
Low Temp. Go to Step 2
Go to Step 6 –
2
Check drive belt condition and tension. Refer to 6A1
Engine Mechanical. To Specification Go to Step 3 Replace drive
belt or
tensioner.
3 Check coolant Boiling Go to Step 4 Go to Step 5
4 Check coolant level. Refer to 3.2 Coolant
Maintenance in this Section. Low Go to Step 10 Go to Step 6
5
Check coolant filler cap. Refer to 3.7 Pressure
Testing – Coolant Filler Cap Pressure Testing in this
Section OK? Go to Step 8
Replace
Coolant filler
cap
6 Check thermostat. Refer to 3.8 Thermostat in this
Section. OK? Go to Step 9 Go to Step 13
7
Check Engine Coolant Temperature (ECT) sensor.
Refer to 6C1 Engine Management General Information. Faulty Replace Go to Step 12
8
Check cooling fan operation. Refer to 6C1 Engine
Management General Information. Operational Go to Step 10 Repair
9
Check for collapsed upper or lower radiator hose. Collapsed Replace Go to Step 13
10 Visual system check Leaks Go to Step 13 Go to Step 11
11 Check coolant concentration. Refer to 3.2 Coolant
Maintenance. To Specification Go to Step 12 Correct
Concentration Level
12 Check radiator core for bent fins, dirt, bugs or other
obstructions. Obstructed Clean or
straighten Go to Step 14
13
Pressure Test cooling system. Refer to 3.7 Pressure
Testing in this Section. Leaks Repair System OK
14
If none of the above require repair, the problem is
complex or of a major nature.
Refer to 4.5 Problems Not Requiring Disassembly of
Cooling System or 4.6 Problems Requiring Disassembly
of Cooling System. – – –

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Engine Management – V6 – General Information Page 6C1-1–2

3.9 Serial Data Communication System ................................................................................................................... 17
3.10 Self Diagnostics System ..................................................................................................................................... 17
3.11 Service Programming System ..................................................................................................... ....................... 17
3.12 Immobiliser System ............................................................................................................................................. 18
4 Component Description and Operation ............................................................................................ .19
4.1 A/C Refrigerant Pressure Sensor ....................................................................................................................... 19
4.2 Brake Pedal Switch Assembly ............................................................................................................................ 19
Stop Lamp and Initial Brake Apply Switch ....................................................................................... ................. 19
Stop Lamp Switch ............................................................................................................................................ 19
Initial Brake Apply Switch ..................................................................................................... ............................ 19
4.3 Barometric Pressure Sensor..................................................................................................... .......................... 20
4.4 Camshaft Position Sensor .................................................................................................................................. 20
4.5 Crankshaft Position Sensor ................................................................................................................................ 21
4.6 Clutch Pedal Switch Assembly – Manual Vehicles Only ............................................................................ ...... 22
4.7 Engine Control Module........................................................................................................................................ 22
4.8 Engine Coolant Temperature Sensor .............................................................................................. ................... 23
4.9 Electric Cooling Fans .......................................................................................................................................... 23
4.10 Engine Oil Level and Temperature Sensor ........................................................................................ ................ 24
Engine Oil Temperature Sensor ......................................................................................................................... 24
Engine Oil Level Sensor ...................................................................................................................................... 25
4.11 Engine Oil Pressure Sensor..................................................................................................... ........................... 25
4.12 Fuel Injectors........................................................................................................................................................ 26
4.13 Fuel Rail Assembly ............................................................................................................. ................................. 27
4.14 Heated Oxygen Sensors .......................................................................................................... ............................ 27
LSF 4.2 Two-step Planar Heated Oxygen Sensors .................................................................................. ......... 27
LSU 4.2 Wide-band Planar Heated Oxygen Sensors ................................................................................. ....... 29
4.15 Ignition Coil and Spark Plug ............................................................................................................................... 31
4.16 Intake Air Temperature Sensor .................................................................................................. ......................... 32
4.17 Knock Sensor ....................................................................................................................................................... 32
4.18 Mass Air Flow Sensor........................................................................................................... ............................... 33
Air Intake System ................................................................................................................................................. 33
Mass Air Flow Sensor........................................................................................................... ............................... 33
Construction ..................................................................................................................................................... 34
Operation ......................................................................................................................................................... 34
5 Abbreviations and Glossary of Terms ............................................................................................ ...35

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Engine Management – V6 – General Information Page 6C1-1–7


Figure 6C1-1 – 4
Legend
1 Camshaft Position (CMP) Sensor
2 Fuel Rail Assembly
3 Fuel Injector (six places)
4 Evaporative Canister Purge (EVAP) Valve 5 Engine Coolant Temperature (ECT) Sensor
6 Engine Oil Level / Temperature Sensor
7 Knock (KS) Sensor (two places)
8 Engine Oil Pressure Sensor

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Engine Management – V6 – General Information Page 6C1-1–9

3 System Operation
The engine control module (ECM) is the control centre of the V6 engine management system. The ECM constantly
monitors and evaluates inputs from various sensors and switches. Based on these inputs, the ECM controls the
operation of the engine management system. Refer to Figure 6C1-1 – 6 for the illustration of the inputs and outputs of
the ECM.

Figure 6C1-1 – 6
3.1 Fuel Delivery System
Fuel System Pressure
W hen the ignition switch is turned on, the ECM energises the fuel pump circuit and the fuel pump runs and builds up
pressure in the fuel system. The fuel pump will continue to operate if the engine is started or as long as the engine is
cranking or running and the ECM detects crankshaft position (CKP) sensor signal pulses. If the CKP sensor signal
pulses stop, the ECM de-energises the fuel pump circuit within two seconds, which stops the fuel pump operation.
The vehicle is fitted with a modular fuel pump and sender assembly that provides delivery of fuel from the fuel tank and
information on the fuel level. The fuel delivery system is a single line, on-demand design. W ith the fuel pressure regulator
incorporated into the modular fuel pump and sender assembly, the need for a return pipe from the engine is eliminated.
The electric fuel pump contained in the modular fuel pump and sender assembly provides fuel at a pressure greater than
the regulated pressure which is supplied to the fuel rail. The fuel is then distributed through the fuel rail to six injectors
located directly above each cylinder’s two intake valves.
Having a single line fuel supply system reduces the internal temperature of the fuel tank by not returning hot fuel from the
engine. In reducing the internal temperature of the fuel tank, lower evaporative emissions are achieved.
Unleaded fuel must be used to ensure correct emission parameters and engine operation. Leaded fuel damages the
emission control system and use of leaded fuel can result in loss of emission warranty. Using unleaded fuel will also
minimise any spark plug fouling and extend engine oil life.

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Engine Management – V6 – General Information Page 6C1-1–12

Battery Voltage Correction Mode
The ECM monitors the battery voltage circuit to ensure the voltage available to the engine management system stays
within the specified range. A low system voltage changes the voltage across the fuel injectors, which affects the fuel
injector flow rate. In addition, a low system voltage fault condition may cause other engine management system
components to malfunction.
The ECM switches to battery voltage correction mode when the ECM detects a low battery voltage fault condition. W hile
in battery voltage correction mode, the ECM performs the following functions to compensate for the low system voltage:
• Increases the injector on-time to maintain the correct amount of fuel being delivered, and
• Increases the idle speed to increase the generator output.
Limp Mode
The programming in the ECM software allows the engine to run in a back-up fuel strategy or limp mode when the ECM
fails to receive signal inputs from critical sensors or when a critical engine management fault condition exists.
The ECM switches to limp mode to enable the vehicle to be driven until service operations can be performed.
Engine Protection Mode
Engine protection mode is engaged to protect engine components from friction damage in the event of an engine over-
temperature condition being detected by the ECM.
W hen the ECM is in engine protection mode, fuel injectors are systematically disabled and re-activated. The injectors
that have been shut down allow the air being drawn into the engine to assist with engine cooling.
Clear Flood Mode
If the engine is flooded with fuel during starting and will not start, the clear flood mode can be manually selected by
depressing the accelerator pedal to wide open throttle (W OT). In this mode, the ECM will completely disable the fuel
injectors, and will maintain this state during engine cranking as long as the ECM detects a W OT condition with engine
speed less than 1,000 rpm.
3.3 Ignition Control System
The electronic ignition system provides a spark to ignite the compressed air / fuel mixture at the correct time. The ECM
maintains correct spark timing and dwell for all engine operating conditions. The ECM calculates the optimum spark
parameters from information received from the various sensors and triggers the appropriate ignition module / coil to fire
the spark plug.
3.4 Starter Motor Operation
The engine control module controls the activation of the start relay in response to inputs from:
• Ignition switch,
• Battery,
• Immobiliser system, and
• Automatic transmission gear selector position / clutch pedal position switch for vehicles with manual transmissions.
3.5 Throttle Actuator Control System
Description
The throttle actuator control (TAC) system is used to improve emissions, fuel economy and driveability. The TAC system
eliminates the mechanical link between the accelerator pedal and the throttle plate and eliminates the need for a cruise
control module and idle air control motor. The TAC system comprises of:

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Engine Management – V6 – General Information Page 6C1-1–24

4.10 Engine Oil Level and Temperature
Sensor
The engine oil level (EOL) and temperature sensor is a dual
purpose sensor and is fitted in the engine sump. It combines
a switch to signal oil level and a thermistor type temperature
sensor to provide oil temperature signal to the ECM.

Figure 6C1-1 – 24
Engine Oil Temperature Sensor
The engine oil temperature sensor is a negative
temperature coefficient (NTC) type. At low engine oil
temperature, the sensor produces a high resistance, whilst
at high temperature the sensor produces a low resistance.
Legend
A Temperature
B Resistance
The ECM provides a 5 V reference signal to the engine oil
temperature sensor and monitors the return signal which
enables it to calculate the engine oil temperature.
Figure 6C1-1 – 25

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