tow ISUZU AXIOM 2002 Service Owner's Manual

6E±116
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description
When the ignition switch is turned ªONº, the powertrain
control module (PCM) will turn ªONº the in-tank fuel
pump. The in-tank fuel pump will remain ªONº as long as
the engine is cranking or running and the PCM is receiving
58X crankshaft position pulses. If there are no 58X
crankshaft position pulses, the PCM will turn the in-tank
fuel pump ªOFFº 2 seconds after the ignition switch is
turned ªONº or 2 seconds after the engine stops running.
The in-tank fuel pump is an electric pump within an
integral reservoir. The in-tank fuel pump supplies fuel
through an in-line fuel filter to the fuel rail assembly. The
fuel pump is designed to provide fuel at a pressure above
the pressure needed by the fuel injectors. A fuel pressure
regulator, attached to the fuel rail, keeps the fuel available
to the fuel injectors at a regulated pressure. Unused fuel
is returned to the fuel tank by a separate fuel return line.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Connect the fuel pressure gauge to the fuel feed line
as shown in the fuel system illustration. Wrap a
shop towel around the fuel pressure connection in
order to absorb any fuel leakage that may occur
when installing the fuel pressure gauge. With the
ignition switch ªONº and the fuel pump running, the
fuel pressure indicated by the fuel pressure gauge
should be 333-376 kPa (48-55 psi). This pressure
is controlled by the amount of pressure the spring
inside the fuel pressure regulator can provide.
3. A fuel system that cannot maintain a constant fuel
pressure has a leak in one or more of the following
areas:

The fuel pump check valve.

The fuel pump flex line.

The valve or valve seat within the fuel pressure
regulator.

The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using
a Tech 2. If an extremely lean condition occurs, the
oxygen sensor(s) will stop toggling. The oxygen
sensor output voltage(s) will drop below 500 mV.
Also, the fuel injector pulse width will increase.
IMPORTANT:Make sure the fuel system is not
operating in the ªFuel Cut-Off Modeº.
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulator
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly as
the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine ªOFFº.16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:

Remove the fuel rail, but leave the fuel lines and
injectors connected to the fuel rail. Refer to
Fuel Rail
Assembly
in On-Vehicle Service.

Lift the fuel rail just enough to leave the fuel injector
nozzles in the fuel injector ports.
CAUTION: In order to reduce the risk of fire and
personal injury that may result from fuel spraying on
the engine, verify that the fuel rail is positioned over
the fuel injector ports and verify that the fuel injector
retaining clips are intact.

Pressurize the fuel system by connecting a 10 amp
fused jumper between B+ and the fuel pump relay
connector.

Visually and physically inspect the fuel injector
nozzles for leaks.
17.A rich condition may result from the fuel pressure
being above 376 kPa (55 psi). A rich condition may
cause a DTC P0132 or a DTC P0172 to set.
Driveability conditions associated with rich
conditions can include hard starting (followed by
black smoke) and a strong sulfur smell in the
exhaust.
20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure
below 333 kPa (48 psi). A lean condition may
cause a DTC P0131 or a DTC P0171 to set.
Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold ), hesitation, poor driveability, lack of
power, surging , and misfiring.
22.Restricting the fuel return line causes the fuel
pressure to rise above the regulated fuel pressure.
Command the fuel pump ªONº with the Tech 2. The
fuel pressure should rise above 376 kPa (55 psi) as
the fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414 kPa
(60 psi). Fuel pressure in excess of 414 kPa (60 psi) may
damage the fuel pressure regulator.
CAUTION: To reduce the risk of fire and personal
injury:

It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge. Refer to
Fuel Pressure Relief Procedure, below.

A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out. Place the towel in
an approved container when the procedure is
completed.

6E±421
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1167 Fuel System Rich During Decel Fuel Cut Off (Bank1)

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any component related DTCs set?Go to
component
DTC charts
Go to Step 3
31. Place the transmission in Park.
2. Using a Tech 2, HO2S 1 voltage while running warm
engine 75
C ± 95
C (167
F ± 203
F) at 1200
RPM.
3. HO2S 1 voltages should vary within the specified
range. (100 ± 900mV)
4. Quickly open the wide open the throttle for a few
seconds.
Did the voltage suddenly rise toward the low end of the
specified range?
100 ± 600 mV
Go to OBD
System
Check
Go to Step 4
41. Disconnect the fuel pump relay and crank the
engine to relieve the fuel pressure.
2. Install the fuel pressure gauge.
3. Start the engine and idle at normal operating
temperature.
4. Disconnect the vacuum line going to the fuel
pressure regulator.
With the engine running, is the fuel pressure within the
specified range?
280 ± 325Kpa
(41 ± 46psi)
Go to OBD
System
Check
Go to Step 5
51. Ignition ªOFFº.
2. Remove the fuel pump relay and replace it with a
fused jumper which will connect the relay's battery
terminal to the terminal leading to the fuel pump
fuse.
3. While the fuel pump is operating, use pliers to slowly
close the return line (do not exceed the first
specified value).
Using the pliers to restrict the return line, can the
fuel pressure be manipulated to exceed the second
value?
Is the fuel pressure gauge reading near the specified
value?
325KPa
(46psi)
414KPa
(60psi)
Refer to
Diagnostic
Aids
Go to Step 6
6Check the following items;

Faulty fuel pump

Incorrect fuel pump

Incorrect fuel being used

Cold fuel
If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairÐ

6E±423
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1169 Fuel System Rich During Decel Fuel Cut Off (Bank2)

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any component related DTCs set?Go to
component
DTC charts
Go to Step 3
31. Place the transmission in Park.
2. Using a Tech 2, HO2S 2 voltage while running warm
engine75 C ± 95 C (167 F ± 203 F) at 1200 RPM.
3. HO2S 1 voltages should vary within the specified
range. (100 ± 900mV)
4. Quickly open the wide open the throttle for a few
seconds.
Did the voltage suddenly rise toward the low end of the
specified range?
100 ± 600 mV
Go to OBD
System
Check
Go to Step 4
41. Disconnect the fuel pump relay and crank the
engine to relieve the fuel pressure.
2. Install the fuel pressure gauge.
3. Start the engine and idle at normal operating
temperature.
4. Disconnect the vacuum line going to the fuel
pressure regulator.
With the engine running, is the fuel pressure within the
specified range?
280 ± 325Kpa
(41 ± 46psi)
Go to OBD
System
Check
Go to Step 5
51. Ignition ªOFFº.
2. Remove the fuel pump relay and replace it with a
fused jumper which will connect the relay's battery
terminal to the terminal leading to the fuel pump
fuse.
3. While the fuel pump is operating, use pliers to slowly
close the return line (do not exceed the first
specified value).
Using the pliers to restrict the return line, can the fuel
pressure be manipulated to exceed the second value?
Is the fuel pressure gauge reading near the specified
value?
325KPa
(46psi)
414KPa
(60psi)
Refer to
Diagnostic
Aids
Go to Step 6
6Check the following items;

Faulty fuel pump

Incorrect fuel pump

Incorrect fuel being used

Cold fuel.
If a problem is found, repair one as necessary.
Was a problem found?
ÐVerify repairÐ

6E±425
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
4. When the engine is idling or at steady cruise, the
HO2S voltage should vary from between
approximately 100 mV to 900 mV. It is possible to
measure a satisfactory fuel pressure at idle even
though the pressure may drop at high flow
requirements. It may be necessary to watch fuel
pressure at high engine load.
5. Wrap a shop towel around the fuel pressure
connector to absorb any small amount of fuel
leakage that may occur when installing gauge.
Ignition ªONº, pump pressure should be 280-320
kPa.
7. Add Caution, Use correct pliers so damage to fuel
lines will not occur.

6E±426
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1171 ± Fuel System Lean During Acceleration

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any component-related DTCs set?
Ð
Go to
component
DTC charts
Go to Step 3
31. Check the vehicle's fuel tank for an adequate
amount of fuel.
2. Add fuel to the vehicle's fuel tank if the tank is almost
empty.
Was fuel added to the vehicle's fuel tank?
ÐGo to Step 4Go to Step 5
41. Place the transmission in park.
2. Using a Tech 2, observe HO2S 1 voltage while
running warm engine 75
C-95
C (167
F-203
F) at
1200 RPM.
3. HO2S 1 voltage should vary within the specified
range.
4. Quickly open the throttle too halfway for a few
seconds.
Did the voltage suddenly rise toward the high end of the
specified range?
100-900 mV
Go to Fuel
System
Electrical Test
Go to Step 5
51. Disconnect the fuel pump relay and crank the
engine to relieve the fuel pressure.
2. Install the fuel pressure gauge.
3. Start the engine and idle at normal operating
temperature.
4. Disconnect the vacuum line going to the fuel
pressure regulator.
With the engine running, is the fuel pressure within the
specified range?
280-325 kPa
(41-46 psi)
Go to OBD
System
Check
Go to Step 6
6Check for restricted fuel lines or restricted in-line filter.
Was a problem found?
ÐVerify repairGo to Step 7
71. Ignition ªOFFº.
2. Remove the fuel pump relay and replace it with a
fused jumper which will connect the relay's battery
terminal to the terminal leading to the fuel pump
fuse.
3. While the fuel pump is operating, use pliers to slowly
close the return line (do not exceed the first
specified value).
Using the pliers to restrict the return line, can the fuel
pressure be manipulated to exceed the second
specified value?
325 kPa
(46 psi)
414 kPa
(60 psi)
Go to
Diagnostic
Aids
Go to Step 8
8Check for:

Faulty fuel pump

Restricted fuel pump strainer (sock)

Incorrect fuel pump

Incorrect fuel being used

Hot fuel
Is the action complete?
ÐVerify repairÐ

6E±555
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
6. Install the fuel rail. Refer to Fuel Rail section.
014RW164
7. Install the common chamber. Refer to Common
Chamber in Engine Mechanical
section.
8. Install the engine cover.
9. Connect the negative battery cable.
Fuel Metering System
Fuel Pressure Relief Procedure
CAUTION: To reduce the risk of fire and personal
injury, there are necessary to relieve the fuel system
pressure before filler and gauge unit servicing the
fuel system components.
CAUTION: After relieving the system pressure, a
small amount of fuel may be released when servicing
fuel lines or connections. Reduce the chance of
personal injury by covering the fuel line fittings with
a shop towel before you disconnect the fittings. The
towels will absorb any fuel that may leak out. When
the disconnect is completed, place the towel in an
approved container.
1. Remove the fuel cap.2. Remove the fuel pump relay from the underhood
relay box. Refer to
Fuel Pump Relay section.
014RY00004
3. Start the engine and allow it to stall.
4. Crank the engine for 30 seconds.
5. Disconnect the negative battery cable.
Fuel Pump Assembly
Removal Procedure
Refer to Fuel Tank In Fuel Pump Relay section.
014RW133

7A±10
AUTOMATIC TRANSMISSION (4L30±E)
Checking Transmission Fluid Level
and Condition
Checking fluid level and condition (color and odor) at
regular intervals will provide early diagnosis information
about the transmission. This information may be used to
correct a condition that, if not detected early, could result
in major transmission repairs.
IMPORTANT:When new, automatic transmission fluid
is red in color. As the vehicle is driven, the transmission
fluid will begin to look darker in color. The color may
eventually appear light brown.
A dark brown color with burnt odor may indicate
excessive fluid deterioration and signal a need for fluid
change.
Fluid Level
When adding or changing fluid, use only DEXRON )±III.
Refer to
Maintenance and Lubrication in General
Information section for maintenance information and
servicing interval.
CAUTION: DO NOT OVERFILL.
Overfilling will cause foaming, loss of fluid, abnor-
mal shifting and possible damage to the transmis-
sion.
1. Park the vehicle on level ground and apply the parking
brake firmly.
2. Check fluid level with engine running at idle.
NOTE: Be sure that transmission fluid temperature is
below 30
C (86
F).
3. Move the selector lever through all gear ranges.
4. Move the selector lever to ªParkº.
5. Let engine idle for 3 minutes and open the overfill
screw (1).
6. Add released transmission fluid until it flows out over
the overfill screw opening.
7. Let engine idle until a fluid temperature between 32
C
(90
F) and 57
C (135
F) is reached, then close the
overfill screw (1).
Torque: 38 Nwm (28 lb ft)
NOTE: To prevent fluid leaks, the overfill screw and oil
drain screws gasket must be replaced each time these
screws are removed.NOTE: Check transmission fluid temperature with scan
tool.
Minimum fluid level " 57
C (135
F)
Maximum fluid level " 32
C (90
F)
242R200001
CAUTION: Do not open overfill screw with engine
stopped.
CAUTION: DO NOT CHECK FLUID LEVEL UNDER
THESE CONDITIONS:

Immediately after driving at sustained highway
speeds.

In heavy city traffic during hot weather.

If vehicle is towing a trailer.
If the vehicle has been operated under these conditions,
shut the engine off and allow the vehicle to ªcoolº for thirty
(30) minutes. After the cool down period, restart the
vehicle and continue from step 2 above.

7A±22
AUTOMATIC TRANSMISSION (4L30±E)
Chart 16: Possible Causes Of
Transmission Fluid Leaks
Before attempting to correct an oil leak, the actual source
of the leak must be determined. In many cases, the
source of the leak may be difficult to determine due to
ªwind flowº around the engine and transmission.
The suspected area should be wiped clean before in-
specting for the source of the leak.Oil leaks around the engine and transmission are gener-
ally carried toward the rear of the vehicle by the air
stream. In determining the source of an oil leak, the fol-
lowing two checks should be made:
1. With the engine running, check for external line
pressure leaks.
2. With the engine off, check for oil leaks due to the
raised oil level caused by drainback of converter oil
into the transmission.
Possible Causes Of Fluid Leaks Due To Sealing Malfunction
240RX008
Legend
(1) Electrical Connector (Main Case) Seal
(2) Transmission Vent (Breather)
(3) Speed Sensor O±Ring
(4) Extension (Adapter) Lip Seal
(5) Extension (Adapter) to Main Case Gasket
(6) Overfill and Oil Drain Screws Gasket
(7) Oil Pan Gasket (Main Case)
(8) Selector Shaft Seal(9) Oil Cooler Connectors (2)
(10) Oil Pan Gasket (Adapter Case)
(11) Converter housing attaching bolts not correctly
torqued
(12) Converter Housing Lip Seal
(13) Line Pressure Tap Plug
(14) Electrical Connector (Adapter Case) Seal
(15) Adapter Case Seal Rings (2)

7A±27 AUTOMATIC TRANSMISSION (4L30±E)
Changing Transmission Fluid
There is no need to change the transmission fluid unless
the transmission is used under one or more of the
following heavy duty conditions.
A. Repeated short trips
B. Driving on rough roads
C. Driving on dusty roads
D. Towing a trailer
If the vehicle is used under these conditions, change the
fluid every 20,000 miles (32,000 km).
1. Place a large drain pan under the oil pan.
2. Remove the transmission oil drain screw (2) and drain
fluid.
3. Tighten drain screw (2).
Torque: 38 Nwm (28 lb ft)
4. Remove the transmission overfill screw (1) and fill
transmission through overfill screw opening, using
DEXRON)±III ATF.
NOTE: Add transmission fluid until it flows out over the
overfill screw opening.
5. Let engine idle until a fluid temperature between 32
C
(90
F) and 57
C (135
F) is reached.
6. Add transmission fluid until it flows out over the overfill
screw opening, then close the overfill screw (1).
Torque: 38 Nwm (28 lb ft)NOTE: To prevent fluid leaks, the overfill screw and oil
drain screws gasket must be replaced each time these
screws are removed.
NOTE: Check transmission fluid temperature with scan
tool.
7. Reset ªOil Life Monitorº data by using Tech 2.
Refer to
Tech 2 OBD II Connection in Transmission
Control System (4L30-E) section.
242R200001
Selector Lever
Inspection
1. Make sure that when the selector lever is shifted from
ªPº to ªLº, a ªclickingº can be felt at each shift position.
Make sure that the gear corresponds to that of the
position plate indicator.
2. Check to see if the selector lever can be shifted as
shown in illustration.
C07RW009
Removal
1. Disconnect battery ground cable.
2. Set ignition Key in ªLOCKº position and selector lever
in ºPº position.
3. Remove knee pads (1), cluster upper cover (2) and
center cluster assembly (3).
740R200021

7A±40
AUTOMATIC TRANSMISSION (4L30±E)
1.Separating the connector and fuel pipe
1. Clean the fuel pipe and connector to remove
mud and other dirt.
2. Pull the black plastic piece toward the
connector. Hold the piece near the connector.
Pull the connector from the fuel pipe.
If the connector and fuel pipe are stuck togeth-
er, jiggle the connector back and forth to loosen
the connector. Do not yank the connector from
the fuel pipe.
141RY00002
141RY00003
3. Tie a vinyl bag around the connector and fuel
pipe to protect them from dirt.
141RY00004
2.Joining the connector and fuel hose
1. Remove the vinyl bag from the connector and
fuel hose. Check that the contact surfaces are
undamaged and free of dirt and other foreign
material. Clean if necessary.
2. Align the axis of the fuel pipe and connector.
Push the connector into the fuel pipe until a
distinct click is heard.
141RY00005