sensor VOLVO XC70 2004 Owner's Manual

2004 VOLVO XC70

pg. 132 Fuel/emissions systems
Fuel system
The fuel system continually compensates for variation in engine load, sp\
eed and temperature. A mass air
flow sensor continuously measures the inducted air and makes rapid adjus\
tments for changes in air
temperature and density, to balance fuel economy, emissions, and engine \
power requirements.
Heated oxygen sensor
This is an emission control system designed to reduce emissions and impr\
ove fuel economy. The heated
oxygen sensor monitors the composition of the exhaust gases leaving the \
engine. The exhaust gas
analysis is fed into an electronic module. This adjusts the air/fuel rat\
io to improve combustion and
reduce the three major pollutants (hydrocarbons, carbon monoxide, and o\
xides of nitrogen (NOx)) via a
three-way catalytic converter.
Crankcase ventilation
The engine is provided with positive crankcase ventilation which prevent\
s crankcase gases from being
released into the atmosphere. Instead, the crankcase gases are routed to\
the intake manifold and
cylinders.
PremAir®
On the surface of the radiator in the engine compartment, there is a spe\
cial coating called PremAir®.
PremAir® works as a catalytic converter, converting most of the ozone\
passing through the radiator into
oxygen, thereby reducing harmful ground-level ozone.
Evaporative control system
The car is equipped with an evaporative control system, which prevents g\
asoline vapor from being
released into the atmosphere.
The system consists of a fuel tank with filler pipe and cap, two rollove\
r valves, a Fill Limit Vent Valve
(FLVV), vapor vent lines, a charcoal canister, a purge line, and a pur\
ge control valve and engine
connections. In addition, there is a pressure sensor connected to the fu\
el tank and a filter-protected
Canister Close Valve (CCV) on the atmospheric side of the canister, fo\
r system diagnosis.
The gasoline vapor is channeled through the rollover valves and the FLVV\
via the vapor vent lines into
the charcoal canister, where it is stored. When the engine is started, t\
he gasoline vapor is drawn from the
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2004 VOLVO XC70
R-models, checking oil level 138
Radio
153
Rain sensor - windshield wipers
37
Reading lights - front/rear
74
Rear fog light
29, 35
Rear reading lights
74
Rear seat backrest
66
Rear window - heated
38
Rearview mirror
41
Refrigerant
47
Refueling
86
Remote central locking system and sideview mirrors
system
41
Remote control - keyless entry system
77
Remote control - Homelink® Universal Transceiver
170
Remote keyless entry system
77
Remote keyless entry system - replacing batteries
78
Remote keyless entry system and driver's seat
57
Removing the seat cushion
66
Replacing bulbs
122-127
Replacing fuses
118
Replacing wiper blades
142
Road assistance
151
Roadholding
96
Roof load - maximum
145
Roof racks
98
S
Safety locks - child
82
Seat belt maintenance
17
Seat belts
2, 3, 14
Seat belts - cleaning
130
Seats - front
56
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