2002 ISUZU AXIOM engine coolant

6E±538
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
On Vehicle
Service Crankshaft Position
(CKP) Sensor
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the electrical connector to the CKP
sensor.
3. Remove one bolt and the CKP sensor from the right
side of the engine block, just behind the mount.
NOTE: Use caution to avoid any hot oil that might drip
out.
TS22909
Inspection Procedure
1. Inspect the sensor O-ring for cracks or leaks.
2. Replace the O-ring if it is worn or damaged.
3. Lubricate the new O-ring with engine oil.
4. Install the lubricated O-ring.
Installation Procedure
1. Install the CKP sensor in the engine block.
2. Install the CKP sensor mounting bolt.
Tighten

Tighten the mounting bolt to 9 N´m (78 lb in.).
TS22909
3. Connect the electrical connector to the CKP sensor.
4. Connect the negative battery cable.
Engine Coolant Temperature
(ECT) Sensor
Removal Procedure
NOTE: Care must be taken when handling the engine
coolant temperature (ECT) sensor. Damage to the ECT
sensor will affect proper operation of the fuel injection
system.
1. Disconnect the negative battery cable.
2. Drain the radiator coolant. Refer to
Draining and
Refilling Cooling System
in Engine Cooling section.
3. Disconnect the electrical connector.
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6E±539
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
4. Remove the ECT sensor from the coolant crossover.
014RY00002
Installation Procedure
1. Apply sealer or the equivalent to the threads of the
ECT sensor.
2. Install the ECT sensor in the coolant crossover.
Tighten

Tighten the ECT sensor to 30 N´m (22 lb ft.).
014RY00002
3. Connect the electrical connector.
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4. Fill the radiator with coolant. Refer to Draining and
Refilling Cooling System
in Engine Cooling section.
5. Connect the negative battery cable.
Heated Oxygen Sensor (HO2S)
Removal Procedure
1. Disconnect the negative battery cable.
2. Locate the four oxygen sensors.
060RW008

6E±558
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
5. Connect the connectors to manifold absolute
pressure sensor, solenoid valve, electric vacuum
sensing valve.
6. Connect the throttle position sensor electrical
connector to throttle body.
7. Install the engine cover.
8. Connect the negative battery cable.
9. Crank the engine until it starts. Cranking the engine
may take longer than usual due to trapped air in the
fuel rail and in the injectors.
Fuel Tank
Removal Procedure
Refer to Fuel Tank In Fuel Pump Relay
014RW134
Throttle Body (TB)
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain the cooling system. Refer to
Cooling System
section.
3. Disconnect the electrical connectors:

Throttle position (TP) sensor.

Intake air temperature (IAT) sensor. Refer to
Intake
Air Temperature Sensor
section.
060RY00014
4. Disconnect the vacuum hose below the air horn.
5. Remove the intake air duct clamp.
6. Disconnect the intake air duct.
7. Disconnect the coolant lines from the throttle body.
8. Remove the bolts from the common chamber.
9. Remove the throttle body from the common chamber.
10. Remove the gasket from the common chamber.
025RY00004
11. Remove the TP sensor. Refer to Throttle Position
(TP) Sensor
section.

6E±559
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Inspection Procedure
NOTE: Do not use solvent of any type when you clean the
gasket surfaces on the intake manifold and the throttle
body assembly. The gasket surfaces and the throttle
body assembly may be damaged as a result.

If the throttle body gasket needs to be replaced,
remove any gasket material that may be stuck to the
mating surfaces of the manifold.

Do not leave any scratches in the aluminum casting.
Installation Procedure
1. Install the TP sensor. Refer to Throttle Position (TP)
Sensor
section.
2. Install the gasket on the common chamber.
3. Install the throttle body on the common chamber.
4. Secure the gasket and the throttle body with the four
bolts.

The vacuum lines must be properly routed under
the throttle body before tightening the mounting
bolts.
Tighten

Tighten the throttle body mounting bolts to 10
N´m (87 lb in).
025RY00004
5. Install the coolant lines.
6. Connect all the vacuum lines.
7. Install the intake air duct.
8. Tighten the intake air duct clamp.9. Connect all the electrical connectors:

Throttle position (TP) sensor.

Intake air temperature (IAT) sensor. Refer to
Intake
Air Temperature Sensor
section.
060RY00020
10. Install the accelerator cable assembly. Refer to
Accelerator Cable in Engine Speed Control System
section.
11. Fill the cooling system. Refer to
Cooling System
section.
12. Install the negative battery cable.

6E±571
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Metri-Pack
Tools Required
J 35689 Terminal Remover
Removal Procedure
Some connectors use terminals called Metri-Pack Series
150. These may be used at the engine coolant
temperature (ECT) sensor.
1. Slide the seal (1) back on the wire.
2. Insert the J 35689 tool or equivalent (3) in order to
release the terminal locking tang (2).
060
3. Push the wire and the terminal out through the
connector. If you reuse the terminal, reshape the
locking tang.
Installation Procedure
Metri-Pack terminals are also referred to as ªpull-to-seatº
terminals.
1. In order to install a terminal on a wire, the wire must be
inserted through the seal (2) and through the
connector (3).2. The terminal (1) is then crimped onto the wire.
061
3. Then the terminal is pulled back into the connector to
seat it in place.

6E±572
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
General Description (PCM and
Sensors)
58X Reference PCM Input
The powertrain control module (PCM) uses this signal
from the crankshaft position (CKP) sensor to calculate
engine RPM and crankshaft position at all engine speeds.
The PCM also uses the pulses on this circuit to initiate
injector pulses. If the PCM receives no pulses on this
circuit, DTC P0337 will set. The engine will not start and
run without using the 58X reference signal.
A/C Request Signal
This signal tells the PCM when the A/C mode is selected
at the A/C control head. The PCM uses this to adjust the
idle speed before turning ªONº the A/C clutch. The A/C
compressor will be inoperative if this signal is not
available to the PCM.
Refer to
A/C Clutch Circuit Diagnosis section for A/C
wiring diagrams and diagnosis for the A/C electrical
system.
Crankshaft Position (CKP) Sensor
The crankshaft position (CKP) sensor provides a signal
used by the powertrain control module (PCM) to calculate
the ignition sequence. The CKP sensor initiates the 58X
reference pulses which the PCM uses to calculate RPM
and crankshaft position.
Refer to
Electronic Ignition System section for additional
information.
0013
Engine Coolant Temperature (ECT) Sensor
The engine coolant temperature (ECT) sensor is a
thermistor (a resistor which changes value based on
temperature) mounted in the engine coolant stream. Low
coolant temperature produces a high resistance of
100,000 ohms at ±40
C (±40
F). High temperature
causes a low resistance of 70 ohms at 130
C (266
F).
The PCM supplies a 5-volt signal to the ECT sensor
through resistors in the PCM and measures the voltage.
The signal voltage will be high when the engine is cold and
low when the engine is hot. By measuring the voltage, thePCM calculates the engine coolant temperature. Engine
coolant temperature affects most of the systems that the
PCM controls.
The Tech 2 displays engine coolant temperature in
degrees. After engine start-up, the temperature should
rise steadily to about 85
C (185
F). It then stabilizes
when the thermostat opens. If the engine has not been
run for several hours (overnight), the engine coolant
temperature and intake air temperature displays should
be close to each other. A hard fault in the engine coolant
sensor circuit will set DTC P0177 or DTC P0118. An
intermittent fault will set a DTC P1114 or P1115.
0016
Electrically Erasable Programmable Read
Only Memory (EEPROM)
The electrically erasable programmable read only
memory (EEPROM) is a permanent memory chip that is
physically soldered within the PCM. The EEPROM
contains the program and the calibration information that
the PCM needs to control powertrain operation.
Unlike the PROM used in past applications, the EEPROM
is not replaceable. If the PCM is replaced, the new PCM
will need to be programmed. Equipment containing the
correct program and calibration for the vehicle is required
to program the PCM.
Fuel Control Heated Oxygen Sensors
The fuel control heated oxygen sensors (Bank 1 HO2S 1
and Bank 2 HO2S 1) are mounted in the exhaust stream
where they can monitor the oxygen content of the exhaust
gas. The oxygen present in the exhaust gas reacts with
the sensor to produce a voltage output. This voltage
should constantly fluctuate from approximately 100 mV to
900 mV. The heated oxygen sensor voltage can be
monitored with a Tech 2. By monitoring the voltage output
of the oxygen sensor, the PCM calculates the pulse width
command for the injectors to produce the proper
combustion chamber mixture.

Low HO2S voltage is a lean mixture which will result in
a rich command to compensate.

High HO2S voltage is a rich mixture which will result in
a lean command to compensate.

6E±574
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
resistance of 100,000 ohms at ±40
C (±40
F). High
temperature causes low resistance of 70 ohms at 130
C
(266
F) . The PCM supplies a 5-volt signal to the sensor
through a resistor in the PCM and monitors the signal
voltage. The voltage will be high when the incoming air is
cold. The voltage will be low when the incoming air is hot.
By measuring the voltage, the PCM calculates the
incoming air temperature. The IAT sensor signal is used
to adjust spark timing according to the incoming air
density.
The Tech 2 displays the temperature of the air entering
the engine. The temperature should read close to the
ambient air temperature when the engine is cold and rise
as underhood temperature increases. If the engine has
not been run for several hours (overnight), the IAT sensor
temperature and engine coolant temperature should read
close to each other. A fault in the IAT sensor circuit will set
DTC P0112 or DTC P0113.
Linear Exhaust Gas Recirculation (EGR)
Control
The PCM monitors the exhaust gas recirculation (EGR)
actual position and adjusts the pintle position accordingly.
The PCM uses information from the following sensors to
control the pintle position:

Engine coolant temperature (ECT) sensor.

Throttle position (TP) sensor.

Mass air flow (MAF) sensor.
Mass Air Flow (MAF) Sensor
The mass air flow (MAF) sensor measures the difference
between the volume and the quantity of air that enters the
engine. ªVolumeº means the size of the space to be filled.
ªQuantityº means the number of air molecules that will fit
into the space. This information is important to the PCM
because heavier, denser air will hold more fuel than
lighter, thinner air. The PCM adjusts the air/fuel ratio as
needed depending on the MAF value. The Tech 2 reads
the MAF value and displays it in terms of grams per
second (gm/s). At idle, the Tech 2 should read between
4-7 gm/s on a fully warmed up engine. Values should
change quickly on acceleration. Values should remain
stable at any given RPM. A failure in the MAF sensor or
circuit will set DTC P0101, DTC P0102, or DTC P0103.
0007
Manifold Absolute Pressure (MAP) Sensor
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum). The
MAP sensor signal voltage to the PCM varies from below
2 volts at idle (high vacuum) to above 4 volts with the
ignition ON, engine not running or at wide-open throttle
(low vacuum).
The MAP sensor is used to determine the following:

Manifold pressure changes while the linear EGR flow
test diagnostic is being run. Refer to
DTC P0401.

Barometric pressure (BARO).
If the PCM detects a voltage that is lower than the
possible range of the MAP sensor, DTC P0107 will be set.
A signal voltage higher than the possible range of the
sensor will set DTC P0108. An intermittent low or high
voltage will set DTC P1107, respectively. The PCM can
detect a shifted MAP sensor. The PCM compares the
MAP sensor signal to a calculated MAP based on throttle
position and various engine load factors. If the PCM
detects a MAP signal that varies excessively above or
below the calculated value, DTC P0106 will set.
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6E±575
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Powertrain Control Module (PCM)
The powertrain control module (PCM) is located in the
passenger compartment below the center console. The
PCM controls the following:

Fuel metering system.

Transmission shifting (automatic transmission only).

Ignition timing.

On-board diagnostics for powertrain functions.
The PCM constantly observes the information from
various sensors. The PCM controls the systems that
affect vehicle performance. The PCM performs the
diagnostic function of the system. It can recognize
operational problems, alert the driver through the MIL
(Check Engine lamp), and store diagnostic trouble codes
(DTCs). DTCs identify the problem areas to aid the
technician in making repairs.
PCM Function
The PCM supplies either 5 or 12 volts to power various
sensors or switches. The power is supplied through
resistances in the PCM which are so high in value that a
test light will not light when connected to the circuit. In
some cases, even an ordinary shop voltmeter will not give
an accurate reading because its resistance is too low.
Therefore, a digital voltmeter with at least 10 megohms
input impedance is required to ensure accurate voltage
readings. Tool J 39200 meets this requirement. The PCM
controls output circuits such as the injectors, fan relays,
etc., by controlling the ground or the power feed circuit
through transistors or through either of the following two
devices:

Output Driver Module (ODM)

Quad Driver Module (QDM)
060RY00068
PCM Components
The PCM is designed to maintain exhaust emission levels
to government mandated standards while providing
excellent driveability and fuel efficiency. The PCM
monitors numerous engine and vehicle functions via
electronic sensors such as the throttle position (TP)sensor, heated oxygen sensor (HO2S), and vehicle
speed sensor (VSS). The PCM also controls certain
engine operations through the following:

Fuel injector control

Ignition control module

ION sensing module

Automatic transmission shift functions

Cruise control

Evaporative emission (EVAP) purge

A/C clutch control
PCM Voltage Description
The PCM supplies a buffered voltage to various switches
and sensors. It can do this because resistance in the
PCM is so high in value that a test light may not illuminate
when connected to the circuit. An ordinary shop
voltmeter may not give an accurate reading because the
voltmeter input impedance is too low. Use a 10-megohm
input impedance digital voltmeter (such as J 39200) to
assure accurate voltage readings.
The input/output devices in the PCM include
analog-to-digital converters, signal buffers, counters,
and special drivers. The PCM controls most components
with electronic switches which complete a ground circuit
when turned ªON.º These switches are arranged in
groups of 4 and 7, called either a surface-mounted quad
driver module (QDM), which can independently control up
to 4 output terminals, or QDMs which can independently
control up to 7 outputs. Not all outputs are always used.
PCM Input/Outputs
Inputs ± Operating Conditions Read

Air Conditioning ªONº or ªOFFº

Engine Coolant Temperature

Crankshaft Position

Exhaust Oxygen Content

Electronic Ignition

Manifold Absolute Pressure

Battery Voltage

Throttle Position

Vehicle Speed

Fuel Pump Voltage

Power Steering Pressure

Intake Air Temperature

Mass Air Flow

Engine Knock

Acceleration Position
Outputs ± Systems Controlled

EVAP Canister Purge

Exhaust Gas Recirculation (EGR)

Ignition Control

Fuel Control

ION Sensing Module

Electric Fuel Pump

Air Conditioning