1997 AUDI A4 fuel

BEFORE cranking the engine at starting RPM
(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.
Pa
ge 9 of 13 Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.2

24-14

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
Pa
ge 10 of 13 Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.2

connector test kit.

For any work affecting the Engine Control
Module (ECM):
BEFORE disconnecting the ECM harness
connector, switch the ignition OFF and WAIT
at least 20 seconds. Failure to do so may
damage the ECM.
DO NOT connect any outside voltage source
to stimulate an output signal at the ECM.
Pa
ge 11 of 13 Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.2

24-15

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:
Pa
ge 12 of 13 Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.2

Avoid working with compressed air whenever
possible.

Avoid moving the vehicle if possible.
Pa
ge 13 of 13 Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.2