Audi 4.2-liter V8 FSI, Обучение по обслуживанию

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Exhaust System
30
Secondary Air System
The secondary air system ensures that the catalytic
converter heats up more quickly and is available sooner
after a cold start.
Principle
Due to the richer air-fuel mixture in the cold start and
warm-up phases, a higher concentration of unburned
hydrocarbons occurs in the exhaust gas. Post-oxidation in
the manifold and header pipe is promoted by secondary-
air injection. The heat dissipated during this process
heats the catalytic converter to operating temperature
within approximately 30 seconds after engine start.
Operating Mode in the Audi Q7
During the warm-up phase, the Engine Control Module
J623 activates Secondary Air Injection (AIR) Pump Motor
V101 via the Secondary Air Injection (AIR) Pump Relay
J299.
The air flow from the secondary air pump opens the
combination valve for secondary air and admits air into
the exhaust system upstream of the catalytic converter.
377_043
Audi Q7 Secondary Air System
Air Filter
Secondary Air
Injection (AIR) Pump
Motor V101
Combination Valves
(self-opening)