warning AUDI A4 1998 B5 / 1.G APB Engine Charge Air System With Turbocharger Workshop Manual

21-9

Turbocharger and charge pressure
regulating valve, checking


Safety notes
Note the following points if test equipment has to
be used during a road test:

WARNING!

Test equipment must always be secured on
the rear seat and operated from there by a
second person.
If test equipment is operated from the front
passenger seat, the occupant could be
injured by the passenger's airbag in an
accident.

Special tools, testers and auxiliary items
Turbocharger tester VAG 1397 A
VAG 1551 Scan Tool or VAG 1552 with cable
VAG 1551/3
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21-13

Charge air pressure regulation,
checking


Special tools and equipment

or
Test requirement:
WARNING!
VAS 5051 with VAG 5051/1VAG 1551 with VAG 1551/3ACoolant Temperature at least 80 C. During a road test in an airbag-equipped vehicle, test equipment
must always be fastened to and operated from the rear seat by a
second technician. 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.
Pa
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21-17

- Check correction factors in display fields 2 to
4.

Display fields

1 2 3 4
Display group 116: Charge air pressure regulation
Display 1 RPM
% % mbar
Indicated Engine speed (RPM)
Correction factor
Fuel Correction factor
Coolant temp. Correction factor
Intake air temp.
Specified value


Note: If display field 2 indicates a correction factor <0
%, fuel quality is probably incorrect.

- Fill tank with prescribed fuel quality.
If display field 3 indicates a correction factor <0
%, coolant temperature is too high (heat warning
lamp lit in instrument cluster) or the Engine
Control Module is receiving an incorrect
temperature signal from the instrument cluster.

- Check coolant temperature display.

Pa
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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pair&id=AUDI.B5.GE05.21.1