Isuzu Trooper (1998-2002 year). Manual - part 350

6E–313

ENGINE DRIVEABILITY AND EMISSIONS

Fuel Gauge Unit

Removal Procedure

1. Disconnect the negative battery cable.
2. Loosen the fuel filler cap.
3. Drain the fuel from the tank.

Tighten

D

Tighten the drain plug to 20 N·m (14 lb ft.).

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4. Disconnect the wiring connector from the fuel gauge

unit.

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5. Remove the fuel gauge unit retaining screws.
6. Remove the fuel gauge unit.

D

Cover or plug the fuel tank to prevent dust, dirt, or
debris from entering the tank.

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Installation Procedure

1. Install the fuel gauge unit.
2. Install the fuel gauge unit retaining screws.

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ENGINE DRIVEABILITY AND EMISSIONS

3. Connect the wiring connector to the fuel gauge unit.

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4. Fill the fuel tank with fuel.

D

Tighten the fuel filler cap.

D

Check for leaks at the fuel gauge unit gasket.

5. Connect the negative battery cable.

Fuel Injectors

Removal Procedure

NOTE: If the fuel injectors are leaking, the engine oil may
be contaminated with fuel.  Check the oil for signs of
contamination and change the oil and the filter if
necessary.

NOTE: Use care in removing the fuel injectors in order to
prevent damage to the fuel injector electrical connector
pins or the fuel injector nozzles.  The fuel injector is an
electrical component and should not be immersed in any
type of cleaner as this may damage the fuel injector.

IMPORTANT:

Fuel injectors are serviced as a complete

assembly only.

1. Disconnect the negative battery cable.
2. Remove the upper intake manifold.  Refer to

Common Chamber in Engine Mechanical..

3. Remove the fuel rail.  Refer to 

Fuel Rail.

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4. Remove the injector retainer clip. 

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5. Remove the fuel injector assembly.
6. Remove the O-ring from the fuel injector.
7. Remove the O-ring backup from the fuel injector .

Inspection Procedure

1. Inspect the O-rings for cracks or leaks.
2. Replace worn or damaged O-rings.
3. Lubricate the new O-rings with engine oil before

installation.

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ENGINE DRIVEABILITY AND EMISSIONS

Installation Procedure

1. Install the O-ring backup on the fuel injector.
2. Install the new O-ring on the fuel injector.
3. Install the fuel injector on the fuel rail.

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4. Use new fuel injector retainer clips to retain the fuel

injector to the fuel rail.

5. Coat the end of the fuel injector with engine oil.
6. Install the fuel rail.  Refer to 

Fuel Rail.

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7. Install the upper intake manifold.  Refer to 

Common

Chamber in Engine Mechanical.

8. Install the engine cover.
9. Connect the negative battery cable.

Fuel Pressure Regulator

Removal Procedure

CAUTION: To reduce the risk of fire and personal
injury, it is necessary to relieve the fuel system
pressure before 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 disconnecting the fittings.  The
towels will absorb any fuel that may leak out.  When
the disconnect is completed, place the towel in an
approved container.

NOTE: Compressed air must never be used to test or
clean a fuel pressure regulator, as damage to the fuel
pressure regulator may result.

NOTE: To prevent damage to the fuel pressure regulator,
do not immerse the pressure regulator in solvent.

1. Depressurize the fuel system.  Refer to 

Fuel Pressure

Relief Procedure.

2. Disconnect the negative battery cable.
3. Remove the fuel pump relay.  Refer to 

Fuel Pump

Relay.

4. Remove the pressure regulator hose from the fuel

pressure regulator.

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ENGINE DRIVEABILITY AND EMISSIONS

5. Remove the two bolts from the protector that secures

the common chamber.

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6. Remove the fuel pressure regulator attaching screw.

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7. Remove the fuel pressure regulator from the fuel rail.

Disassembly Procedure

1. Remove the O-ring from the fuel pressure regulator.
2. Loosen the swivel nut.
3. Remove the fuel return line from the fuel pressure

regulator.

4. Remove the O-ring from the fuel return line.

D

The O-ring may be left inside the fuel pressure
regulator instead of on the fuel return line.

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Assembly Procedure

1. Install a new O-ring on the fuel return line.
2. Install the fuel return line on the fuel pressure

regulator.

NOTE: Do not over-tighten the swivel nut on the fuel
pressure regulator.  The fuel pressure regulator can be
damaged and fuel may leak if the swivel nut is
over-tightened.

3. Tighten the swivel nut.
4. Install a new O-ring on the fuel pressure regulator.