Secondary Air Injection System
The secondary air injection system produces a reoxidation of the exhaust gasses in the warm-up phase, by injecting fresh air into the exhaust tract.
The secondary air injection is activated on cold starts. It switches off when oxygen sensor regulation sets in. After a cold start, the engine is powered with a rich mixture (lambda < 1).
The system is activated in this phase. The oxygen contained in the injected air reacts with the hot exhaust gas in the exhaust manifold right behind the exhaust valves.
Oxidation converts the pollutants CO and HC into CO2 and H2O. The exhaust temperature increases.
The oxygen sensor and catalytic converter attain their operating temperatures more rapidly.
Oxygen sensor regulation is activated earlier.
The system consists of the following components:
X 14 XE, X 16 XE
1 Delay valve
2 Vacuum hose
3 Electric switchover valve
4 Secondary air pump
5 Secondary air filter
6 Bracket for secondary air pump
7 Vacuum hose, electric switchover valve/combination valve
8 Connection hose, secondary air pump/combination valve
9 Combination valve
10 Injection pipe support
11 Gasket, combination valve
12 Injection pipe
13 Pressure hose
LHD = Left-hand drive vehicle
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