Acura 2012 TL - Manual (Page 628)

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
come out the tailpipe. The exhaust
emissions control systems are
separate from the crankcase and
evaporative emissions control
systems. 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 emissions control systems
The PGM-FI system uses sequential
multiport fuel injection. It has three
subsystems: air intake, engine
control, and fuel control. The
powertrain control module (PCM) in
automatic transmission vehicles or
the engine control module (ECM) in
manual transmission vehicles 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.
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 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
This system constantly adjusts the
ignition timing, reducing the amount
of HC, CO, and NOx produced.
2
2
Exhaust Emissions Controls Replacement Parts
PGM-FI System
Three Way Catalytic Converter
Exhaust Gas Recirculation (EGR)
System
Ignition Timing Control System
Emissions Controls
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T
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chnical
Inf
or
mat
ion
are covered by warranties separate
from the rest of your vehicle. Read
your warranty manual for more
information.
is burned.
2012 TL