2007 HONDA PILOT Air intake

Airflow is divided between
the floor vents and the defroster
vents at the base of the windshield.
Air flows from the defroster
vents at the base of the windshield.
When you select or ,
the system automatically switches to
fresh air mode and turns on the A/C.
In this case, you cannot turn the A/C
off.
When you select , the system
au tomatically switches to fresh air
mode and turns on the A/C.
When you select , the system
au tomatically switches to fresh air
mode and turns on the A/C.
This button turns the rear window
def ogger of f and on (see page ).
Use the mode control dial or button
to select the vents the air flows from.
Some air will flow from the
dashboard corner vents in all modes.
Each time you press the MODE
button, the display shows the mode
selected.
Air flows from the center
and corner vents in the dashboard.
Airf low is divided between
the vents in the dashboard and the
f loor vents.
Air f lows f rom the f loor
vents.
When the indicator in the button is
on, air f rom the vehicle’s interior is
sent throughout the system again.
When the indicator is off, air is
brought in f rom the outside of the
vehicle (fresh air mode).
The outside air intakes f or the
heating and cooling system are at
the base of the windshield. Keep this
area clear of leaves and other debris.
Thesystemshouldbeleftinfresh
air mode under almost all conditions.
Keeping the system in recirculation
mode, particularly with the A/C of f ,
can cause the windows to fog up.
Switch to recirculation mode when
driving through dusty or smoky
conditions, then return to fresh air
mode.
77
On EX and EX-L models
On EX and EX-L models
On LX models
Vents, Heating, and A/C
Rear Window Def ogger Button
Mode Control
Recirculation Button
108

ÎÎIn
Canada, Honda vehicles comply
with the Canadian emission
requirements, as specified in an
agreement with Environme nt
Canada, at the time they are
manufactured.
Your vehicle has a positive
crankcase ventilation system. This
keeps gasses that build up in the
engine’s crankcase from going into
the atmosphere. The positive crankcase
ventilation valve routes
them from the crankcase back to the
intake manifold. They are then
drawn into the engine and burned.
As gasoline evaporates in the fuel
tank, an evaporative emissions
control canister filled with charcoal
adsorbs the vapor. It is stored in this
canister while the engine is off. After
the engine is started and warmed up,
the vapor is drawn into the engine
and burned during driving.
The onboard refueling vapor
recovery (ORVR) system captures
the fuel vapors during refueling. The
vapors are adsorbed in a canister
filled with activated carbon. While
driving, the fuel vapors are drawn
into the engine and burned off.
The
burning of gasoline in your
vehicl e’s engine produces several by-
products. Some of these are carbon
monoxide (CO), oxides of nitrogen
(NOx), and hydrocarbons (HC).
Gasoline evaporating from the tank
also produces hydrocarbons. Con-
trolling the production of NOx, CO,
and HC is important to the environ-
ment. Under certain conditions of
sunlight and climate, NOx and HC
re act to form photochemical ‘‘smog.’’
Carbon monoxide does not contri-
bute to smog creation, but it is a
poisonous gas. The
United States Clean Air Act
sets standards for automobile
emissions. It also requires that
automobile manufacturers explain to
owners how their emissions controls
workandwhattodotomaintain
them. This section summarizes how
the emissions controls work.
Scheduled maintenance is on page .
234
Crankcase Emissions Control
System Evaporative Emissions Control
System
Onboard Ref ueling Vapor
Recovery
The Clean Air Act
Emissions Cont rols
Technical Inf ormation
295

The exhaust emissions controls
include f our systems: PGM-FI,
ignition timing control, exhaust gas
recirculation, and three way catalytic
converter. These f our 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 f rom the crankcase and
evaporative emissions control
systems.
The PGM-FI system uses sequential
multiport f uel injection.
It has three subsystems: air intake,
engine control, and f uel 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 operating
conditions.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
Honda replacement parts or their
equivalent f or repairs. Using lower
qualitypartsmayincreasethe
emissions f rom your vehicle.
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. 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.
2
2
Exhaust Emissions Controls Replacement Parts
PGM-FI Syst emT hree Way Cat alyt ic Convert er
Ignit ion T iming Cont rol Syst em
Exhaust Gas Recirculat ion (EGR)Syst em
Emissions Cont rols
296