sensor Acura MDX 2003 Owner's Manua

Two f actors normally contribute to
causing corrosion in your vehicle:Moisture trapped in body cavities.
Dirtandroadsaltthatcollectsin
hollows on the underside of the
vehicle stays damp, promoting
corrosion in that area.
Removal of paint and protective
coatings f rom the exterior and
underside of the vehicle. Repair chips and scratches in the
paint as soon as you discover them.
Inspect and clean out the drain
holes in the bottom of the doors
and body.
Check the f loor coverings f or
dampness. Carpeting and f loor
mats may remain damp f or a long
time, especially in winter. This
dampness can eventually cause
the f loor panels to corrode.Use a high-pressure spray to clean
the underside of your vehicle. This
is especially important in areas
that use road salt in winter. It is
also a good idea in humid climates
and areas subject to salt air. Be
caref ul of the ABS wheel sensors
and wiring at each wheel.
Have the corrosion-preventive
coatings on the underside of your
vehicle inspected and repaired
periodically.
Many corrosion-preventive measures
are built into your Acura. You can
help keep your vehicle f rom
corroding by perf orming some
simple periodic maintenance:
1.
2.
Corrosion Prot ect ion
Appearance Care357

If you are planning to take your
Acura outside the U.S., contact the
tourist bureaus in the areas you will
betravelingintofindoutaboutthe
availability of unleaded gasoline with
theproperoctanerating.
If unleaded gasoline is not available,
be aware that using leaded gasoline
in your Acura will af f ect perf or-
mance and fuel mileage, and damage
its emissions controls. It will no
longer comply with U.S. and
Canadian emissions regulations, and
will be illegal to operate in North
America. To bring your vehicle back
into compliance will require the re-
placement of several components,
such as the oxygen sensors and the
three way catalytic converter. These
replacements are not covered under
warranty.
Driving in Foreign Countries
T echnical Inf ormation396

The exhaust emissions controls
include f our 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 f rom 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 f or more informa-
tion.
The PGM-FI System uses sequential
multiport f uel injection.
It has three subsystems: Air Intake,
Engine Control, and Fuel Control.
The Powertrain Control Module
(PCM) uses various sensors to
determine how much air is going
into the engine. It then controls how
much f uel to inject under all operat-
ing conditions. This system constantly adjusts the
ignition timing, reducing the amount
of HC, CO, and NOx produced.
The Exhaust Gas Recirculation
(EGR) system takes some of the
exhaust gas and routes it back into
the intake manif old. Adding exhaust
gas to the air/f uel mixture reduces
the amount of NOx produced when
the f uel is burned.
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 emissions control systems are
designed and certif ied 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 f or repairs. Using lower
qualitypartsmayincreasethe
emissions f rom your vehicle.
2
2
Exhaust Emissions Controls Replacement Parts
PGM-FI Syst emIgnit ion T iming Cont rol Syst em
Exhaust Gas Recirculat ion (EGR)Syst em
Three Way Catalytic Converter
Emissions Cont rols
T echnical Inf ormation398