Exhaust Emission Control System (Pulse Secondary Air Injection System); Noise Emission Control System (U Type Only) - Honda VTR1000F Service Manual

GENERAL INFORMATION
EXHAUST EMISSION CONTROL SYSTEM (PULSE SECONDARY AIR INJECTION SYSTEM)
(SW, AR, IIG type only)
The exhaust emission control system consists of a secondary air supply 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 the pulse secondary air injection (PAIR) control valve and PAIR check valves. 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 afterburn in the exhaust system.
No adjustment to the pulse secondary air injection system should be made, although periodic inspection of the components
is recommended.
PAIR CONTROL
VALVE
PAIR CHECK --t+-------~~/~
VALVE
NOISE EMISSION CONTROL SYSTEM (U type only)
AIR CLEANER
<;:==J
FRESH AIR
• EXHAUST GAS
TAMPERING WITH THE NOISE CONTROL SYSTEM IS PROHIBITED: law may prohibit: (1) The removal or rendering
inoperative by any person, other than for purposes of maintenance, repair or replacement, of any device or element of
design incorporated into any new vehicle for the purpose of noise control prior to its sale or delivery to the ultimate pur-
chaser or while it is in use; (2) the use of the vehicle after such device or element of design has been removed or rendered in-
operative by any person.
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