Honda 2003 ST1300lA, Owner'S Manual

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Emission Control Systems
Source of Exhaust Emissions
The combustion process produces carbon monoxide, oxides of nitrogen, and
hydrocarbons. Control of hydrocarbons and oxides of nitrogen is very important
because, under certain conditions, they react to form photochemical smog when
subjected to sunlight. Carbon monoxide does not react in the same way, but it is
toxic.
Honda Motor Co., Ltd. utilizes various systems to reduce carbon monoxide and
hydrocarbons.
Exhaust Emission Control System
The exhaust emission control system includes a secondary air injection system,
PGM-FI system, two warm-up oxidation catalysts, two three-way catalytic
converters, and two heated oxygen sensors.
No adjustment to these systems should be made although periodic inspection of
the components is recommended.
PGM-FI System
The PGM-FI system uses sequential multiport fuel injection. It has four
subsystems: Air Intake, Engine Control, Fuel Control, and Exhaust Control.
The Engine Control Module (ECM) uses various sensors to determine how
much air is going into the engine. It then controls how much fuel to inject under
all operating conditions.
Ignition Timing Control System
The system constantly adjusts the ignition timing, reducing the amount of HC,
CO and NOx produced.
Secondary Air Injection System
Secondary air injection system which introduces filtered air into the exhaust
gases in the exhaust port. The secondary air injection system helps improve
emission performance.
Three- Way Catalytic Converters
The three-way catalytic converters are in the exhaust system. Through chemical
reactions, they convert HC, CO, and NOx in the engine's exhaust to carbon
dioxide
dinitrogen and water vapor.
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Technical Information