sensor AUDI A4 1998 B5 / 1.G AWM Engine Charge Pressure Leak Test Workshop Manual

21-17

WARNING!

Use only approved air fittings to adapt shop
air supply line to VAG 1687 tester.

Special tool VAG 1687/1 pressure adapter,
installing (1.8L Turbo)

- Separate intake hose from Mass Air Flow (MAF)
sensor assembly.

Special tool VAG 1687/1 pressure adapter, installing (2.7L BiTurbo)
Repair Manual, Maintenance; Air cleaner housing, cleaning; Air cleaner element, replacing
- Insert VAG 1687/1 pressure adapter in intake hose -black arrow- using
existing clamp (as shown).
- Remove crankcase ventilation tube from intake hose at -white arrow-.
- Remove upper air cleaner housing and hoses to intake manifold as
necessary

- Insert VAG 1687/1 pressure adapter in intake hose -white arrow- using
existing clamp (as shown).
- Disconnect engine crankcase ventilation hose from intake manifold -
black arrow-.
-
Plug intake manifold fitting (for crankcase ventilation hose) with
appropriate hose and metal plug using clamps supplied with VAG
Pa
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ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.GE06.21.2

21-39


Charge Air Pressure sensor -G31-,
checking

Special tools and equipment

VAG 1526 A
VAG 1594 A
VAG 1598/31
VAS 5051 with VAS 5051/1
- or
VAG 1551 with VAG 1551/3 A
Pa
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ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.GE06.21.2

21-40

Test requirements:

Vehicle diagnostic, testing and information
system VAS 5051 or VAG 1551Scan Tool
connected.

Test sequence

Note:
The Charge Air Pressure sensor -G31- and the
wiring connections are monitored by the engine
control module.

- Read Diagnostic Trouble Code (DTC) memory
of engine control module.
If a DTC relating to the Charge Air Pressure
sensor -G31- is displayed:

Checking power supply

- Disconnect connector -arrow- on charge pressure sender.
Pa
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ge pressure leak test with VAG 1687
11/21/2002 htt
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If specified value is attained:
Checking signal wire - Check for open circuit and short to positive or Ground in following
wiring connections: Connector
contact
Test box VAG 1598/31
1 108
3 98
- Repair any open/short circuit as necessary.
- Attach connector from charge air pressure sensor.
- Attach multimeter for voltage test to socket 101 and socket 108 of test
box.
- Start engine and run at idling speed.
Specified value: approx. 1.90 V
- Bring engine to speed by spontaneous acceleration.Specified value: 2.00...3.00 V
Pa
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ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.GE06.21.2

21-43
If specified values are not attained:

If the wiring is OK: - Check for open circuit and short to positive or Ground in following
wiring connection: Connector
contact
Test box VAG 1598/31
4 101
- Repair any open/short circuit as necessary.
- Replace Charge Air Pressure sensor -G31-.
Pa
ge 34 of 34 Char
ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.21.2