exhaust Acura MDX 2002 User Guide

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
genuine Acura replacement parts or
their equivalent f or repairs. Using
lowerqualitypartsmayincreasethe
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
T echnical Inf ormation
Emissions Cont rols
349
01/09/07 12:50:56 31S3V610_354

A defective three way catalytic
converter contributes to air pollution,
and can impair your engine’s per-
f ormance. Follow these guidelines to
protect your vehicle’s three way
catalytic converter.Keep the engine tuned-up.
Have your vehicle diagnosed and
repaired if it is misf iring, back-
f iring, stalling, or otherwise not
running properly.
Always use unleaded gasoline.
Even a small amount of leaded
gasoline can contaminate the
catalyst metals, making the three
way catalytic converter inef f ective.
The three way catalytic converter
must operate at a high temperature
for the chemical reactions to take
place. It can set on f ire any com-
bustible materials that come near it.
Parkyourvehicleawayfromhigh
grass, dry leaves, or other f lamma-
bles. The three way catalytic converter
contains precious metals that serve
as catalysts, promoting chemical
reactions to convert the exhaust
gasses without af f ecting the metals.
The catalytic converter is ref erred to
as a three-way catalyst, since it acts
on HC, CO, and NOx. A replacement
unit must be an original Acura part
or its equivalent.
Three Way Catalytic Converter
T echnical Inf ormation350
T T
H
H R
REEE
E W
WA AY
Y C
CAA T
TA
A L
LYYT TI
ICC C
COON NVVE
ER
RT TE
ER
R
01/09/07 12:51:03 31S3V610_355

Î
..............................
Bulbs, Halogen .295
................................
Cancel Button .174
............................
Capacities Chart .342
.............
Carbon Monoxide Hazard .56
..........................
Cargo Area Light .119
.............................
Carrying Cargo .203
Cassette Player
............................................
Care .168
...........................
Operation .139,165
..............
CAUTION, Explanation of .ii
...................................
CD Changer .143
.......................................
CD Player .159
........................
Certif ication Label .340
............................................
Chains .292
Change Oil
........................................
How to .263
......................................
When to .252
....................
Changing a Flat Tire .315
............
Changing Engine Coolant .267
...
Charging System Indicator .62,328
............
Checklist, Bef ore Driving .209
..................
Childproof Door Locks .88
.....................................
Child Saf ety .21 .......................................
Child Seats .21
..........
Tether Anchorage Points .42
....................
Cleaner Element, Air .275
Cleaning
....................
Aluminum Wheels .307
...................................
Carpeting .308
......................................
Exterior .306
.........................................
Fabric .309
.......................................
Interior .308
.......................................
Leather .309
...................................
Seat Belts .309
...........................................
Vinyl .309
....................................
Windows .310
...............
Climate Control System .122
......................................
Coat Hook .116
.....................
Code, Audio System .170
........................
CO in the Exhaust .348
........................................
Coin Box .116
............
Cold Weather, Starting in .210
..............................
Compact Spare .314
...............
Consumer Inf ormation .354
.............
Controls, Instruments and .59
Coolant
........................................
Adding .265
....................................
Checking .199
.........................
Proper Solution .265 ...................................
Replacing .267
...................
Temperature Gauge .68
....................
Corrosion Protection .311
Crankcase Emissions Control
........................................
System .348
............
Cruise Control Operation .172
..........
Customer Relations Of f ice .354
................
DANGER, Explanation of .ii
...................................
Dashboard .2,60
................
Daytime Running Lights .73
............
Def ects, Reporting Saf ety .356
................
Def ogger, Rear Window .77
..............
Def rosting the Windows .128
....................................
Dimensions .342
...............
Dimming the Headlights .72
Dipstick
..........
Automatic Transmission .271
..................................
Engine Oil .198
..........................
Directional Signals .74
........
Disc Brake Wear Indicators .220
.....................
Disposal of Used Oil .264
Doors
..............
Locking and Unlocking .82
Index
C
D
II
01/09/07 12:52:20 31S3V610_365

CONT INUED
............................
Fabric, Cleaning .309
...................................
Fan, Interior .126 Features, Comfort and
..............................
Convenience .121
....................
Filling the Fuel Tank .195
Filters
...............................................
Air .275
.......................
Air Conditioning .285
...............................................
Oil .263
.............
Flashers, Hazard Warning . 76
...................
Flat Tire, Changing a . 315
Fluids ..........
Automatic Transmission . 271
..........................................
Brake .273
..........................
Power Steering .274
..................
Windshield Washer . 270
FM Stereo Radio ...................................
Reception .157
........................................
Fog Lights .77
...................
Folding the Third Seat . 96
.....
Foreign Countries, Driving in . 347
..........................
Four-way Flashers .76
..............................
Economy, Fuel .200
............
Emergencies on the Road . 313
.............
Battery, Jump Starting . 323
...........
Brake System Indicator . 331
................
Changing a Flat Tire . 315
.....
Charging System Indicator . 328
..................
Checking the Fuses . 333
.....
Low Oil Pressure Indicator . 327
...
Malf unction Indicator Lamp . 329
..................
Overheated Engine . 325
.........................
Emergency Brake .106
......................
Emergency Flashers .76
......................
Emergency Towing .338 .......................
Emissions Controls .348
Engine ....
Coolant Temperature Gauge . 68
.................................
Drive Belts .285
Malf unction Indicator ................................
Lamp .62, 329
........
Oil Pressure Indicator . 62,327
..............
Oil, What Kind to Use . 261
...............................
Overheating .325
............................
Specif ications .343
............................
Speed Limiter .215
.......................................
Starting .210
......................
Ethanol in Gasoline .346
.
Evaporative Emissions Controls . 348
...............................
Exhaust Fumes .56
Exhaust Gas Recirculation ........................................
System .349
Expectant Mothers, Use of Seat ........................................
Belts by .19
..................
Exterior, Cleaning the . 306
....................
Lockout Prevention . 83
......................
Power Door Locks .82
..........
DOT Tire Quality Grading . 344
.....................................
Drive Belts .285
...........
Driver and Passenger Safety . 5
...........................................
Driving .207
....................................
Economy .200
.........................
In Bad Weather .224
................
In Foreign Countries . 347
..................
Dust and Pollen Filter . 285
Index
E
F
III
01/09/07 12:52:26 31S3V610_366