1996 AUDI A4 ignition

24-25

- Compare coding with coding variation table
Page 01
-93
.

- Switch ignition off.

- Pull rubber gasket forward.

- Remove plenum cover forward.

- Remove cover for E-box (in plenum chamber).

Installing
Installation is performed in the reverse sequence. However note the
following:
Note:
At the first learning (adaptation) phase during the "Engine-Basic Setting"
the engine might run a little rough at idle and bucks/jerks a little while
driving. - Carefully lever off the retainer bar with a screwdriver -arrow-.
- Release connectors on engine control module and disconnect
connectors.
- Remove engine control module.
Pa
ge 28 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU04.24.1

24-37

Note:
A rise in pressure (due to fuel expansion) when
the engine is at operating temperature is normal.

- Start the engine and run at idling speed.

- Switch ignition off after the pressure has built-
up. At the same time close pressure gauge cut-
off tap (lever at 90 to through flow direction). If the pressure does not drop, the following faults
are possible:

Union between pressure gauge and fuel supply
pipe leaking
Supply pipe leaking at fuel tank
Return valve in fuel pump leaking

Repair Manual, Fuel Supply System, Repair
Group 20


Note:
When the cut-off tap is closed the pressure
gauge will indicate the pressure downstream of
Pa
ge 43 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.FU04.24.1

24-41

- Switch ignition on. The diode test lamp should
light up.

- If diode test lamp does not light up, test for open
circuits in wiring between contact 1 and fuse for
injectors. If necessary, rectify open circuit.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations
- If diode test lamp lights up, test activation of
injectors.

C - Testing activation of injectors

- Remove plug connector from the injector which
is to be tested.

Specified value: the diode test lamp should start flashing.
Note:
Diode test lamps with a low current draw continue to glow faintly between - Connect diode test lamp VAG 1527 between the battery positive
terminal (+) and contact 2 on the connector.
- Operate starter for a few seconds (the engine can be allowed to start).
Pa
ge 48 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1

24-50

- Activate remote control VAG1348/3 A for 30
seconds.

- When all three fuel injectors from the first bank
of cylinders have been activated, place the three
measuring glasses on a level surface.

Specified value for each fuel injector: 135 ... 165
ml

- If measured value for one or more of fuel
injectors is outside tolerance range, switch off
fuel pump (switch ignition off) and replace faulty
fuel injector Page 24
-53
, also observe notes
on Page 24
-53
.
Pa
ge 60 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
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pair&id=AUDI.B5.FU04.24.1

24-56

B - Checking voltage supply and activation of
fuel pump relay

Note:
Activation of the fuel pump relay can also be
tested using the final control diagnosis Page
01
-75
.

- Remove fuel pump relay -J17 from central
electrics, relay position 4.

Checking voltage supply

- Switch ignition on.

Specification: approx. battery voltage in each case
Electrical Wiring Diagrams, Troubleshooting & Component Locations - Connect hand-held multimeter VAG1526 between Ground (GND) and
relay panel contact 19 (B+; terminal 15 from ignition switch).
Disconnect, then re-connect between Ground (GND) and relay panel
contact 17 (permanent B+; terminal 30 from battery).
- If values are not as specified, rectify open circuit.
Pa
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(MFI
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11/22/2002 htt
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play?action=Goto&t
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pair&id=AUDI.B5.FU04.24.1

24-63


Note:
Ground (GND) from the ECM is present at terminal 3 of connector.
If specified value is not obtained, check wire connections Page 24
-74
. - Connect multimeter to terminal 2 and terminal 3 of connector for
voltage measurement.
- Operate starter briefly.
Specification: approx. battery voltage

If specified value is not obtained, check wire connections Page 24
-74
. - Connect multimeter to terminal 3 and terminal 1 of connector for
voltage measurement.
- Switch ignition on.
Specification: approx. 5 volts.
Pa
ge 73 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1

24-66


Note:
Ground (GND) from the ECM is present at terminal 3 of connector.
If specified value is not obtained, check wire connections Page 24
-74
. - Connect multimeter to terminal 2 and terminal 3 of connector for
voltage measurement.
- Operate starter briefly.
Specification: approx. battery voltage

If specified value is not obtained, check wire connections Page 24
-74
. - Connect multimeter to terminal 3 and terminal 4 of connector for
voltage measurement.
- Switch ignition on.
Specification: approx. 5 volts.
Pa
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(MFI
) system, servicin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU04.24.1

- Switch ignition off.
Pa
ge 80 of 90 Motronic 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.FU04.24.1