Honda 1992 Accord Coupe Owner's Manual page 155

Emission Controls (cont'd)
Engine Exhaust Controls
The engine exhaust emission control systems are designed to
control combustion during idle, acceleration, cruise, and deceleration.
These systems are entirely separate from the crankcase and
evaporative emission control systems described previously.
PGM-FI System
The PGM-FI system consists of three independent sub-systems;
Air Intake, Electronic Control, and Fuel Control, thus allowing
more accurate control of air/fuel ratios under all operating
conditions. The Electronic Control Unit (ECU) detects the amount
of air drawn into the cylinders and determines the amount of fuel
to be injected to provide the optimum air/fuel ratio for all engine
needs.
Ignition Timing Control System
This system automatically controls the ignition timing to reduce
the amount of HC and NOx.
Catalytic Converter
The catalyst is used to convert hydrocarbons (HC), carbon
monoxide (CO) and oxides of nitrogen (NOx) in the exhaust gas,
to carbon dioxide (CO
Exhaust Gas Recirculation (EGR)
The EGR system is designed to control the formation of oxides of
nitrogen (NOx) caused when fuel mixture burns at high
temperature. It works by recirculating exhaust gas through the
EGR valve and intake manifold into the combustion chambers
where it reduces peak temperature by diluting the air/fuel mixture.
), dinitrogen (N ) and water vapor.
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