2003 VOLVO XC70
pg. 130 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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2003 VOLVO XC70
engine warm up and cooling.
Changing coolant
Normally, the coolant does not need to be changed. If the system must be\
drained, consult your Volvo
retailer.
NOTE: Do not top off with water only. This reduces the rust-protective and ant\
ifreeze qualities of the
coolant and has a lower boiling point. It can also cause damage to the c\
ooling system if it should freeze.
Top off with Volvo Genuine Coolant/Antifreeze only.
CAUTION:
The cooling system must always be kept filled to the correct level. If i\
t is not kept filled, there can be
high local temperatures in the engine which could result in damage. Diff\
erent types of antifreeze/coolant
may not be mixed.
WARNING!
Never remove the radiator cap while the engine is warm. Wait until the c\
ar
cools.
pg. 132 Emissions maintenance
Periodic maintenance helps minimize emissions
Periodic maintenance will help keep your vehicle running well. Your Warr\
anty and Service Records
Information booklet provides a comprehensive periodic maintenance schedu\
le up to 150,000 miles
(240,000 km) of vehicle service. The schedule includes components that\
affect vehicle emissions. This
page describes some of the emission-related components.
Engine air filter
The engine air filter cleans particles from air entering the engine. Rep\
lace the engine air filter cartridge
with a new one every 37,500 miles (60,000 km) under normal driving con\
ditions. Replace the cartridge
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2003 VOLVO XC70
Engine compartment
1 Expansion tank - coolant
2 Power steering fluid reservoir
3 Washer fluid reservoir
4 Dipstick - engine oil
5 Radiator/cooling fan
6 Oil filler cap - engine
7 Brake fluid reservoir
8 Relay/fuse box
9 Air cleaner
10 Battery ( in the cargo compartment) WARNING!
The cooling fan may start or continue to operate (for up to 6 minutes)\
after the engine has been
switched off.
pg. 135 Engine oil
Oil quality
Meeting minimum ILSAC specification GF-2, including ACEA A1, API SJ, SJ/\
CF and SJ/Energy
Conserving. Your Volvo has been certified to standards using ILSAC oil s\
pecification GF-2 5W/30.
Volvo recommends use of oil with a quality rating equal to or higher tha\
n ILSAC GF-2. Equivalent and
better oils include ACEA A1, API SJ, SJ/CF, and SJ/Energy conserving. Lo\
wer quality oils may not
offer the same fuel economy, engine performance, or engine protection. \
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