AUDI A4 1998 B5 / 1.G AFC Engine Fuel Supply System Components Workshop Manual

20-1


Fuel supply system
components, removing and
installing

WARNING!

Always be sure to comply with applicable
safety precautions when working on the fuel
system page 20
-3 .
Pay attention to rules of cleanliness page 20
-
2 .
Adjusting accelerator pedal cable page 20
-
15
.

Notes:

Hose connections are secured with clamp-type,
screw-type, spring-type clamps.
Always replace clamp-type with spring-type or
screw-type clamps.
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20-2

Rules of cleanliness


CAUTION!

Whenever carrying out work on the fuel
supply and fuel injection systems, carefully
observe the following five rules of
cleanliness.
1 - Thoroughly clean fuel system line and hose
connections and the surrounding area before
disconnecting.
2 - Place removed components on a clean
surface and cover. Use plastic sheeting or paper.
Do not use fluffy rags that could leave lint!
3 - Carefully cover over or seal any components
that have been opened if repairs are not carried
out immediately.
4 - Install only clean parts:

Do not remove replacement parts from the
packaging until immediately before they are to
be installed.

Do not use parts that have been stored without
packaging (e.g. in toolboxes, etc.).
5 - When the fuel system is opened:
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Avoid working with compressed air whenever
possible.

Avoid moving the vehicle if possible.
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20-3

Safety precautions


WARNING!

When removing and installing the fuel pump
or fuel level sensor from a filled or partially
filled fuel tank:

BEFORE beginning repairs, the suction pipe
of an exhaust extraction system must be
located near the fuel tank opening so that
escaping fuel vapors can be immediately
carried away.
If no exhaust extraction system is available,
a radial fan (motor located outside airflow)
with volume of at least 15 m3/hr (9 cfm) may
be used.
Wear fuel-resistant gloves whenever working
with open parts of the fuel system.

Be sure the ignition is switched OFF, when:
Disconnecting fuel injection system wiring
Connecting or disconnecting test equipment
leads

BEFORE cranking the engine at starting RPM
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(such as for compression testing) disable the
ignition and fuel injection systems:

Disconnect the ignition coil power output
stage.
Disconnect harness connectors from all fuel
injectors.
After the work is completed, erase
Diagnostic Trouble Code (DTC) memory.
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20-4

CAUTION!

BEFORE disconnecting the battery:

Stop the engine.
Be sure the ignition is switched OFF (also
applies when connecting the battery). Failure
to do so may damage the Engine Control
Module (ECM).
Be sure of the proper radio code (for vehicles
equipped with coded anti-theft radio).

Be sure the battery negative (-) cable is
disconnected, when:
Working on the electrical system
Resistance (spot) welding or electric arc
welding anywhere on the vehicle.

When connecting and disconnecting
electrical test equipment (LED voltage tester,
multimeter, etc.):
Be sure the ignition is switched OFF.
Use correct adapters from the VW 1594
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connector test kit.
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20-5

Flange and fuel level sensor, removing
and installing


Observe safety measures page 20
-3

Pay attention to rules of cleanliness page 20
-2 .

WARNING!

Fire hazard. DO NOT smoke or work near
heaters or have anything in the area that can
ignite fuel!

- Switch ignition on.

- Observe fuel gauge.

CAUTION!

The fuel tank should not be more than 2/3
full. Empty fuel tank, if necessary, using an
approved fuel cart.
Determine correct radio anti-theft coding
before disconnecting the battery.

Removing
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- Disconnect battery Ground (GND) strap.

- Remove cover for fuel pump module flange
(under luggage compartment trim).

- Disconnect harness connector for fuel level
sensor and fuel pump.
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20-6


Installing
_________________________________________________________
Front-wheel-drive vehicles:
All-wheel-drive vehicles:
_________________________________________________________ - Detach blue return line and feed line.
- Use special tool 3217 to loosen sealing ring.
- Carefully pull flange out and detach.
- Unclip fuel level sensor and remove.
- Installation is in reverse order of removal.
- Fuel level sensor wiring must be routed between return line and fuel
tank housing.
- Fuel level sensor wiring must be routed between line of fuel transfer
pump and fuel tank housing.

- When installing, make sure that arrows are aligned.
Note different alignment arrows for FRONT-wheel-drive and
QUATTRO
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