Audi V8 Service page 34

Engine - Motronic Subsystems
Secondary air inlet valve N112
The secondary air inlet valve is an electro-
pneumatic valve. It is activated by the Motro-
nic control unit and controls the combination
valve.
It releases the vacuum stored in the reservoir
to open the combination valve.
Atmospheric pressure is released to close the
combination valve.
Energised
Not energised
Combination valve
The combination valve is bolted to the
secondary air duct of the cylinder head.
The vacuum from the secondary air inlet
valve causes the air channel between the
secondary air pump and the secondary duct
of the cylinder head to open.
At the same time, the valve prevents hot
exhaust gases from entering and then
damaging the secondary air pump.
Valve open
Fresh air from
secondary air
pump
34
Filter cap
Atmosphere
Vacuum in
control line from
secondary air inlet
valve
SSP207_019
To secondary
air duct
To combination
valves
Valve closed
SSP207_018
Exhaust gas
To vacuum reservoir
SSP207_016
Atmospheric
pressure in control
line from secondary
air inlet valve