Acura 2003 NSX, Owner'S Manual

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The exhaust emissions controls
include four systems: PGM-FI,
Ignition Timing Control, Exhaust
Gas Recirculation and Three Way
Catalytic Converter. These four
systems work together to control the
engine’s combustion and minimize
the amount of HC, CO, and NOx that
comes out the tailpipe. The exhaust
emissions control systems are
separate from the crankcase and
evaporative emissions control
systems.
The PGM-FI System uses sequential
multiport fuel injection. It has three
subsystems: Air Intake, Engine
Control, and Fuel 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.
This system constantly adjusts the
ignition timing, reducing the amount
of HC, CO, and NOx produced.
The three way catalytic converter is
in the exhaust system. Through
chemical reactions, it converts HC,
CO, and NOx in the engine’s exhaust
to carbon dioxide (CO ), dinitrogen
(N ), and water vapor.
The Exhaust Gas Recirculation
(EGR) system takes some of the
exhaust gas and routes it back into
the intake manifold. Adding exhaust
gas to the air/fuel mixture reduces
the amount of NOx produced when
the fuel is burned.
During engine warm-up, air is
pumped into the exhaust to reduce
emissions when the engine is cold.
The emissions control systems are
covered by warranties separate from
the rest of your car. Read your
warranty manual for more informa-
tion.
The emissions control systems are
designed and certified to work to-
gether in reducing emissions to
levels that comply with the Clean Air
Act. To make sure the emissions
remain low, you should use only new
Acura replacement parts or their
equivalent for repairs. Using lower
quality parts may increase the
emissions from your car.
2
2
Exhaust Emissions Controls
Replacement Parts
PGM-FI System
Ignition Timing Control System
Three Way Catalytic Converter
Exhaust Gas Recirculation (EGR)
System
Secondary Air Injection System
Emissions Controls
Technical Inf ormation
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