2000 AUDI A4 ignition

20-1


Fuel supply system, servicing
guidelines

Safety precautions


WARNING!

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

BEFORE beginning work, place exhaust
extraction system suction pipe near fuel tank
opening so escaping fuel vapors can be
immediately sucked off.
If no exhaust extraction system is available,
use a radial fan (with motor located outside
airflow) with volume of at least 9 cfm.
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.
Pa
ge 1 of 8 Fuel su
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ly system, servicin
g guidelines
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.GE04.20.1

BEFORE cranking the engine at starting RPM
(such as compression testing) disable the
fuel injection and ignition 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.
Pa
ge 2 of 8 Fuel su
pp
ly system, servicin
g guidelines
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE04.20.1

20-3

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 VW 1594
Pa
ge 4 of 8 Fuel su
pp
ly system, servicin
g guidelines
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.GE04.20.1

20-5
Observe following points before working on the
fuel supply system

CAUTION!

Obtain the radio Anti-theft code from the
customer before disconnecting the Battery
Ground strap.

With ignition switched OFF, disconnect Battery
Ground strap.
Open the fuel filler cap briefly and close
again.
Observe the following precautions when
removing or installing components from a filled or
partially filled fuel tank.

WARNING!

Empty the fuel tank before removal! If it is not
empty, the weight and sloshing fuel could
lead to injury, component damage or possible
fuel spillage.
Fuel tank must not be filled more than
1/3
maximum.

Reduce fuel quantity using fuel cart, if
Pa
ge 7 of 8 Fuel su
pp
ly system, servicin
g guidelines
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE04.20.1