Audi V8 Service page 30

Engine - Motronic Subsystems
Fitting location of vacuum reservoir,
Audi A8
Fitting location of vacuum reservoir,
Audi A6
30
The vacuum required to control the variable
intake manifold and the secondary air system
is provided by two vacuum reservoirs. If a
vacuum exists in the intake manifold, the
reservoirs are evacuated via a non-return
valve.
SSP217_051