ignition AUDI A3 1999 8L / 1.G AEB ATW Engines Turbocharger System Workshop Manual

21-6

Test conditions:

Check DTC memory Repair Manual, 1.8
Liter 4-Cyl. 5V Turbo Fuel Injection &
Ignition, Repair Group 01
Perform output diagnostic test mode
(function 03)
Minimum engine oil temperature: 60 C
(140 F)

All vacuum connections are free of leaks

Test procedure

- Using T-fitting, connect VAG1397A turbocharger tester test hose to
front of intake manifold.
- Guide test hose over rear corner of hood through right window opening
into vehicle interior.
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21-9

Note:
For vehicles with automatic transmission the
charge air pressure test may not always provide
a definitive reading of proper charge air pressure
regulation. If pressure readings are at the lower
end of the specified range, measure charge air
pressure control via load signal Page 21
-10
.

All vehicles:
If measured value is above or below specification
Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 24.

Note:
If no charge air exists and a rumbling sound is
heard from the engine compartment, the causes
are as follows:

Charge pressure bypass valve
malfunctioning.
Vacuum line to charge pressure bypass valve
leaking or disconnected.
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