Exhaust Emission Control System (Pulse Secondary Air Injection System) - Honda Activa SCV110 Service Manual Digest

EXHAUST EMISSION CONTROL SYSTEM (PULSE SECONDARY AIR INJECTION SYSTEM)

The exhaust emission control system consists of a pulse secondary air injection system which introduces filtered air into the exhaust
gases at the exhaust port. Fresh air is drawn into the exhaust port whenever there is a negative pressure pulse in the exhaust system.
This charge of fresh air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocarbons and
carbon monoxide into relatively harmiess carbon dioxide and water vapor.
This model has the pulse secondary air injection (PAIR) control valve and PAIR check valve. PAIR check valve prevents reverse air flow
through the system. The PAIR control valve reacts to high intake manifold vacuum and will cut off the supply of fresh air during engine
deceleration, thereby preventing after burn in the exhaust system.
No adjustment to the pulse secondary air injection system should be made, although periodic inspection of the components is
recommended.
PULSE SECONDARY AIR INJECTION
(PAIR) CHECK VALVE
CARBURETOR
EXHAUST PORT
GENERAL INFORMATION
PULSE SECONDARY
AIR INJECTION (PAIR)
CONTROL VALVE
FRESH AIR
VACUUM AIR
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