Volkswagen Passat 1995 Official Factory Repair Manual page 2173

Secondary Air Injection (AIR) system
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Secondary Air Injection (AIR)
system
CAUTION!
Observe the following for all installations,
especially in engine compartment due to lack
of room:
Route lines of all types (e.g. for fuel,
hydraulic, EVAP canister system, coolant
and refrigerant, brake fluid, vacuum) and
electrical wiring so that the original path is
followed.
Watch for sufficient clearance to all moving
or hot components.
Shift selector lever into position -P- and
engage parking brake before working with
the engine running.
Function
Air is blown behind the exhaust valves by the
Secondary Air Injection (AIR) system during a
cold start. Thereby, the emission gas is enriched
with oxygen, initiating a secondary combustion
and thereby shortening the warm-up phase of the
catalytic converter. Activation occurs from
Motronic Engine Control Module (ECM) -J220-
via Secondary Air Injection (AIR) Pump Relay -
J299- to Secondary Air Injection (AIR) Solenoid
Valve -N112- to the combination valve.
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