Honda Magna VF750C Service Manual page 35

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 introd uces filtered air i nto the
exhaust gases i n 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 i njection control valves with bu ilt-in check valves . The PAI R check valves prevent
reverse air flow through the syste m . The pulse secondary air i njection 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 syste m .
No adjustments t o t h e secondary air supply system should b e made, although periodic inspection o f t h e components is recom­
mended .
(1 I
FRONT PU LSE SECON DARY A I R I NJECTIO N ( PA I R )
C O N T R O L VALVE
(4) EXHAUST PORT
1 - 28
(2) AIR CLEA N E R