1996 AUDI A4 warning

24-9

Safety precautions


WARNING!

Fire hazard! Do not smoke, work near
heaters or open flame, or have anything
nearby that could ignite fuel. The fuel system
is under pressure. Before opening, cover
connections with a rag, and open carefully to
release pressure.
When driving or riding in an airbag-equipped
vehicle, NEVER hold the scan tool or other
test equipment in your hands or lap while in
motion. Objects between you and the airbag
increase the risk of injury in an accident.
During a test drive in an airbag-equipped
vehicle, test equipment must always be
fastened to and operated from the rear seat
by a second technician.
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11/23/2002 htt
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24-10

WARNING!

Be alert when working on or near the engine
and ignition wires. High secondary ignition
voltage can cause serious personal injury
and damage vehicle components.

DO NOT touch or disconnect ignition system
wires when the engine is running or being
cranked at starting RPM.
DO NOT operate the starter if fuel injectors
are removed.

Be sure the ignition is switched OFF, when:
Disconnecting or connecting the battery,
ignition wires, or test equipment leads
Disconnecting fuel injection system wiring
Washing the engine or engine
compartment.

BEFORE cranking the engine at starting RPM
(e.g. for compression testing) disable ignition
and fuel injection systems:
Disconnect connector for ignition coil power
Pa
ge 10 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-102

Fuel injectors, checking


WARNING!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything nearby that
could ignite fuel. The fuel system is under
pressure. Before opening, cover connections
with a rag, and open carefully to release
pressure.
Activating fuel injectors via output Diagnostic
Test Mode (DTM) page 01-51


Required special tools and test equipment

VAG1598/22 test box
Multimeter US1119 (Fluke 83 or equivalent)
VAG1527B LED voltage tester
VW1594 connector test kit
Wiring diagram

Test requirements

Pa
ge 130 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-106

Fuel injectors, checking for leakage


WARNING!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything nearby that
could ignite fuel. The fuel system is under
pressure. Before opening, cover connections
with a rag, and open carefully to release
pressure.

Required special tools and test equipment

VW1594 connector test kit
VAG1348/3A remote control connection
VAG1348/3-2 adapter cable
VAG1602 fuel analyzer

Test requirement
Fuel pressure regulator OK page 24
-111

Pa
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(MFI
) and i
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11/23/2002 htt
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play?action=Goto&t
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e=re
pair&id=AUDI.B5.FU03.24.1

24-111

Fuel pressure, fuel pressure regulator
and residual fuel pressure, checking

The fuel pressure regulator controls the fuel
pressure depending on intake manifold
pressure.

WARNING!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything nearby that
could ignite fuel. The fuel system is under
pressure. Before opening, cover connections
with a rag, and open carefully to release
pressure.

Required special tools and test equipment

Pressure tester VAG1318
Adapter 1318/7
Adapter 1318/10
Adapter 1318/13

Test requirements
Fuel pump delivery rate OK; checking:
Pa
ge 142 of 166 Motronic Multi
port Fuel In
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(MFI
) and i
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-116

Evaporative Emissions (EVAP) canister
purge regulator valve, checking


WARNING!

Whenever carrying out work on the fuel
supply and/or fuel injection systems, read
and carefully follow the Cautions, Warnings,
and rules of cleanliness page 24-9 .

Note:
Component locations page 24
-1

Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable

Test conditions
Engine coolant temperature at least 80 C
(176 F)

Function check

- Connect VAG1551 or VAG1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) page 01
-8 .
Pa
ge 151 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1