Acura 2005 NSX - Owner's Manual - Manual (Page 210)

The exhaust emissions controls
include five systems: PGM-FI,
ignition timing control, exhaust gas
recirculation, secondary air injection
system and three way catalytic
converter. These five 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 emissions control systems are
covered by warranties separate from
the rest of your vehicle. Read your
warranty manual for more informa-
tion.
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 ), nitrogen
(N ), and water vapor.
The emissions control systems are
designed and certified to work
together 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 vehicle.
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.
During engine warm-up, air is
pumped into the exhaust to reduce
emissions when the engine is cold.
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.
2
2
Emissions Controls
Exhaust Emissions Controls
Replacement Parts
PGM-FI System
Three Way Catalytic Converter Ignition Timing Control System
Secondary Air Injection System
Exhaust Gas Recirculation (EGR)
System
208
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