Honda Magna VF750C, Service Manual

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General Information
Exhaust Emission Control System (Pulse Secondary Air Injection System)
California type only
The exhaust emission control system consists of a pulse secondary air injection system which introduces filtered air into the
exhaust gases in 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 harmless carbon dioxide and water vapor.
This model has two pulse secondary air injection control valves with built-in check valves . The PAI R check valves prevent
reverse air flow through the system. The pulse secondary air injection control valve reacts to high intake manifold vacuum
and will cut off the supply of fresh air during engine deceleration, thereby preventing afterburn in the exhaust system.
No adjustments to the secondary air supply system should be made, although periodic inspection of the components is recom­
mended .
(1 I
FRONT PU LSE SECON DARY A I R I NJECTIO N ( PAIR)
CONTROL VALVE
(4)
EXHAUST PORT
1-28
(2) AIR CLEANER