Afterburner system components (Audi A6 C5)

2.0a. Components of the afterburning system:
1 - electric motor of the air pump of the afterburning system
2 - air pump relay of the afterburning system
3 - Engine control unit
4 - valve for supplying fresh air to the exhaust valves (right cylinder head)
5 - vacuum valve of the afterburning system
6 - check valve
7 - to the intake manifold
8 - valve for supplying fresh air to the exhaust valves (left cylinder head)
9 - vacuum receiver