fuel pressure ISUZU TF SERIES 2004 Manual PDF

6C-2 ENGINE FUEL (6VE1 3.5L)
General Description







RTW36CLF000301
Legend (8) Fuel Rail Left
(1) Fuel Filler Cap (9) Intake Air Port Left Bank
(2) Fuel Tank (10) Fuel Pressure Control Valve
(3) Rollover Valve (11) Common Chamber
(4) Fuel Pump and Sender Assembly (12) Duty Solenoid Valve
(5) Fuel Filter (13) Throttle Valve
(6) Fuel Rail Right (14) Canister
(7) Intake Air Port Right Bank (15) Evapo Control Valve

ENGINE FUEL (6VE1 3.5L) 6C-3
Fuel Metering
The Engine Control Module (ECM) is in complete
control of this fuel delivery system during normal driving
conditions.
The intake manifold function, like that of a diesel, is
used only to let air into the engine. The fuel is injected
by separate injectors that are mounted over the intake
manifold.
The Barometric Pressure (BARO) sensor measures the
changes in the barometric pressure which result from
engine load and speed changes, which the BARO
sensor converts to a voltage output.
This sensor generates the voltage to change
corresponding to the flow of the air drawn into the
engine.
The changing voltage is transformed into an electric
signal and provided to the ECM.
With receipt of the signals sent from the BARO sensor,
Intake Air Temperature sensor and others, the ECM
determines an appropriate fuel injection pulse width
feeding such information to the fuel injector valves to
effect an appropriate air/fuel ratio.
The Multiport Fuel Injection system utilizes an injection
system where the injectors turn on at every crankshaf
t
revolution. The ECM controls the injector on time so
that the correct amount of fuel is metered depending on
driving conditions.
Two interchangeable “O" rings are used on the injecto
r
that must be replaced when the injectors are removed.
The fuel rail is attached to the top of the intake manifold
and supplies fuel to all the injectors.
Fuel is recirculated through the rail continually while the
engine is running. This removes air and vapors from the
fuel as well as keeping the fuel cool during hot weathe
r
operation.
The fuel pressure control valve that is mounted on the
fuel rail maintains a pressure differential across the
injectors under all operating conditions. It is
accomplished by controlling the amount of fuel that is
recirculated back to the fuel tank based on engine
demand.
See Section “Driveability and Emission" for more
information and diagnosis.

6C-4 ENGINE FUEL (6VE1 3.5L)
Fuel Filter
Removal
CAUTION: When repair to the fuel system has been
completed, start engine and check the fuel system
for loose connection or leakage. For the fuel system
diagnosis, see Section “Driveability and Emission".
1. Disconnect the battery ground cable.
2. Loosen slowly the fuel filler cap.
NOTE: To prevent spouting out fuel to change the
pressure in the fuel tank.
NOTE: Cover opening of the filler neck to prevent any
dust entering.
3. Disconnect the quick connector into the fuel tube
from the fuel filter.
NOTE: Cover the quick connector to prevent any dus
t
entering and fuel leaking.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.
4. Pull off fuel filter from holder to side member side.
Inspection
1. Replace the fuel filter if the fuel leaks from fuel filter
body or if the fuel filter body itself is damaged.
2. Replace the filter if it is clogged with dirt o
r
sediment.
Installation
1. Install the filter to holder from side member side.
NOTE: Attend direction of fuel filter. (1) to engine side
(2) to fuel tank side.
NOTE: Verify to hang holder hook to fuel filter.


NOTE: Verify to hang holder hook to fuel filter.




RTW36CSH000301
2. Connect the quick connector from the fuel tube to
the fuel filter.
NOTE: Pull of the left checker into the fuel pipe.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.
3. Tighten fuel filler cap until at least one click are
heard.
4. Connect the battery ground cable.
Inspection
After installation, start engine and check for fuel
leakage.
In–Tank Fuel Filter
The filter is located on the lower end of fuel pickup tube
in the fuel tank. It prevents dirt from entering the fuel
pipe and also stops water unless the filter is completely
submerged in the water. It is a selfcleaning type, no
t
requiring scheduled maintenance. Excess water and
sediment in the tank restricts fuel supply to the engine,
resulting in engine stoppage. In such a case, the tank
must be cleaned thoroughly.

ENGINE FUEL (6VE1 3.5L) 6C-5
Fuel Pump Flow Test
If reduction of fuel supply is suspected, perform the
following checks.
1. Make sure that there is fuel in the tank.
2. With the engine running, check the fuel feed pipe
and hose from fuel tank to injector for evidence o
f
leakage. Retighten, if pipe or hose connection is
loose. Also, check pipes and hoses for squashing
or clogging.
3. Insert the hose from fuel feed pipe into a clean
container, and check for fuel pump flow rate.
4. Connect the pump relay terminals (2) with a
jumper wire (1) as shown and start the fuel pump
to measure delivery.




RTW36CSH000201
CAUTION: Never generate sparks when connecting
a jumper wire.

Delivery Delivery
15 seconds 0.38 liters minimum
If the measure value is out of standard, conduct the
pressure test.
Pressure test
For the pressure test to the fuel system, see Section 6E
“Fuel Control System".

ENGINE FUEL (6VE1 3.5L) 6C-7
3. Remove the retainer ring (7) from the fuel tank
with the removal tool 5-8840-2602-0.




140R100035
4. Remove slowly the fuel pump (4) from the fuel
tank as no bend float arm.
NOTE: Cover opening for the fuel pump on fuel tank to
prevent any dust enthering.
5. Discard fuel pump seal (8) because it cannot be
reusable.
Installation
1. Clean the seal surface of the fuel tank and the fuel
pump.
NOTE: If there is dust on the seal surface, it becomes
cause of fuel leak.
2. Install the new fuel pump seal (8) to opening of the
fuel tank as along the groove.
3. Install slowly the fuel pump (4) into the fuel tank as
no bend float arm.
4. Set flange of the fuel pump on fuel pump seal as
mating convexity of the fuel pump and reentrant o
f
the fuel tank.
5. Lock slowly the retainer ring (7) to the fuel tank
with the remover tool 5-8840-2602-0.
6. Connect the quick connector (10) into the evapo
tube to fuel pump.
7. Connect the quick connector (6) into the fuel tube
to fuel pump.
NOTE: Pull off the left ckecker into the fuel pipe.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.

8. Check leak.
Methed of leak check.
(1) Plug end of quick connector and breather hose
(Pull off the breather hose from fuel tank) and
tighten fuel filler cap until at least one click are
heard.
(2)
Apply water soap around the fuel pump seal
area.
(3) Pressure air into the fuel tank from end o
f
breather pipe at 5psi (34.3 kPa/2.8kgf/cm2)
over 15 seconds.
(4) Verify no bubbles around the fuel pump seal
area.
8. Install the fuel tank assembly (9).
NOTE: Refer to “Install the fuel tank” in this section.

6C-8 ENGINE FUEL (6VE1 3.5L)
Fuel Tube / Quick – Connector Fittings
Precautions
 Do not light a match or create a flame.
 Keep flames away from your work area to preven
t
flammable materials from catching fire.
 Disconnect battery ground cable to preven
t
electrical shorts.
 Pre-treat piping system or associated parts from
thermal damage or from spattering when welding
or similar heat-generating work.
Cautions During Work




140R100032
Legend
(1) O-ring
(2) Port
(3) Connector
(4) Plastic Tube

Do not expose the assembly to battery electrolyte or do
not wipe the assembly with a cloth used to wipe off spil
t
battery electorolyte.
Piping that has been splattered with battery electrolyte
or battery electrolyte soaked cloth that was wiped on the
piping cannot be used.
Removal
1. Open the fuel cap to relieve the fuel pressure in the
tank.
Use compressed air to remove any dirt on the fuel
quick connect fittings prior to disconnecting the
fittings.




141R100002
When disconnecting the fuel pipe, cover the area
with a cloth to prevent fuel from splashing as the
fuel pipe may still have some pressure in it.
2. For removal of the quick connector, hold the quick
connector in one hand, and pull out the connento
r
with the other hand while pressing the square
relieve button of the connector, as illustrated.






140R100037
NOTE: Do not use tools of any kind. Only use bare
hands when disconnecting the connector. Use a
lubricant (light oil) and/or push and pull the connecto
r
until the pipe is disconnected.
Cover the connectors that was removed with a
plastic bag, to prevent dust or rain water from
entering.

ENGINE FUEL (6VE1 3.5L) 6C-9




140R100028
Reuse of Quick–Connector
 Replace the port and connector if scratch, dent or
crack is found.
 Remove any dirt build up on the port when installing
the connector. Replace the connector, if there is any
forms of rust, dent, scratch.
 After cleaning the port, insert it straight into the
connector until it clicks. After it clicks, try pulling a
t
49N (5kgf) it out to make sure that it is not drawn
and is securely locked.




140R100036

Assembling Advice
By applying engine oil or light oil to the pipe, port makes
pipe assembly easier. The pipe assembly should take
place immediately after applying oil (to prevent dus
t
from sticking to the pipe surface –which may
decrease sealing ability).
Test/Inspection After Assembling
1. Reconnect the battery negative cable.
2. Turn the ignition key to the “ON" position and listen
for pump start-up sound. Inspect for leaks, the
fuel pressure will increase as the fuel pump is
actuated.
3. Perform leak inspection (step 2) several times.
4. Start the engine and observe the engine idle speed.
The presence of dirt in the fuel system may affec
t
the fuel injection system.

6C-12 ENGINE FUEL (6VE1 3.5L)
Removal
CAUTION: When repair to the fuel system has been
completed, start engine and check the fuel system
for loose connection or leakage. For the fuel system
diagnosis, see Section “Driveability and Emission".
1. Disconnect battery ground cable.
2. Loosen slowly the fuel filler cap.
NOTE: To prevent spouting out fuel to change the
pressure in the fuel tank.
NOTE: Cover opening of the filler neck to prevent any
dust entering.
3. Jack up the vehicle.
4. Support underneath of the fuel tank with a lifter.
5. Remove the inner liner of the wheel house on rea
r
left side.
6. Remove fasten bolt to the filler neck from the
body.
7. Disconnect the quick connector (8) into the fuel
tube from the fuel pipe and the evapo tube from
evapo joint connector.
NOTE: Cover the quick connector to prevent any dus
t
entering and fuel leaking.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.
8. Remove fasten bolt (1) to the tank band and the
tank band (2).
9. Disconnect the pump and sender connector on the
fuel pump and remove the harness from weld clip
on the fuel tank.
10. Lower the fuel tank (6).
NOTE: When the fuel tank is lowered from the vehicle,
don’t scratch each hose and tube by around other pars.


Installation
1. Rise the fuel tank into position.
NOTE: Ensure hoses and tubes do not foul on othe
r
component.
2. Connect the pump and sender connector to the
fuel pump and install harness to into the plastic clip
welded to the top of the fuel tank..
NOTE: The connector must be certainly connected
against stopper.
Ensure tank band anchor mates with guide hole on
frame.
3. Install the tank band to fasten bolt.
Torque: 68 N




m (6.9kg




m/50 lb ft)
NOTE: The anchor of the tank band must be certainly
installed to guide hole on frame.
4. Connect the quick connector from the fuel tube to
the fuel pipe and the evapo tube from evapo join
t
connector.
NOTE: Pull off the left checker into the fuel pipe.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.
5. Install the filler neck to the body by bolt.
6. Install the inner liner of the wheel house on rea
r
side.
7. Remove lifter to support underneath of the fuel
tank.
8. Put back the vehicle.
9. Tigten the filler cap until at least three clicks are
heard.
10. Connect the battery ground cable.

6C-14 ENGINE FUEL (6VE1 3.5L)
Fuel Filler Cap
General Description
A vacuum valve and pressure valve are built into the
fuel filler cap which adjusts the fuel pressure in the fuel
tank to prevent fuel tank damage.



RTW36CSH000401
Legend
(1) Pressure Valve
(2) Vacuum Valve
(3) Seal Ring

Inspection
The fuel filler cap must be inspected for seal condition.
The fuel filler cap must be replaced if found defective
CAUTION: A replacement fuel filler cap must be the
same as the original. The fuel filler cap valve was
designed primarily for this application and must be
replaced with the same type or decreased engine
performance may occur.

6E-4 3.5L ENGINE DRIVEABILITY AND EMISSIONS
THROTTLE POSITION SENSOR (TPS)........... 6E-371
IDLE AIR CONTROL (IAC) VALVE ................... 6E-371
HEATED OXYGEN SENSOR (HO2S) .............. 6E-372
EVAP CANISTER PURGE VALVE
SOLENOID ....................................................... 6E-373
FUEL PRESSURE RELIEF ............................... 6E-374
FUEL RAIL ASSEMBLY .................................... 6E-374
FUEL INJECTORS ............................................ 6E-375
FUEL PRESSURE REGULATOR ..................... 6E-377
IGNITION COIL ................................................. 6E-379
SPARK PLUGS ................................................. 6E-380
SPECIAL TOOLS .............................................. 6E-382