Vacuum Hoses In The Audi Rs4 - Audi 4.2-litre V8 FSI Service Training

Air circulation system

Vacuum hoses in the Audi RS4

The conventional method of supplying vacuum to
the brake servo and the engine components is
problematic in the case of FSI engines.
Secondary air pump
Variable intake manifold
change-over valve N335
Hot-film air mass
meter
Suction jet pump
(entrainment pump)
with integrated non-
return valve
Intake manifold flap
air flow control valve
N316
Vacuum units for
intake manifold flaps
Secondary air
inlet valve N112
Non-return valve
Vacuum pump for
brakes V192
26
Vacuum reservoir
This means that connecting a vacuum line down-
stream of the throttle valve would offer little pros-
pect of success because, in many engine operating
situations, the wide open throttle valve would result
in low mass flow rates and vacuum in the intake
manifold being.
Filter housing flap
Air filter
Brake servo Non-return valve with
brake servo pressure
sensor G294
Vacuum unit for combination valve
Activated charcoal canister
solenoid valve 1 N80
Activated charcoal
canister
B
A
Brake servo
relay J569