Volvo 2001 C70, Operation And Care Manual

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inspected at 60,000 miles (96,000 km) and thereafter, at 30,000 mile (48,000 km) intervals.
Cabin air filter
Replace the cabin air filter with a new one at 15,000 mile (24,000 km) intervals. Volvo recommends replacing the
filter more often if the car is driven under dirty and dusty conditions. The filter cannot be cleaned and therefore should
always be replaced with a new one.
pg. 110 Fuel/emissions systems
Fuel system
The fuel system is allelectronic and is microprocessorcontrolled. It can continually compensate for variation in engine
load, speed and temperature to give the best economy and power. A mass air flow sensor measures the inducted air. In
this way the system can make instantaneous adjustments for changes in air temperature or density, thus always
assuring the best economy with the lowest possible exhaust emissions.
Heated oxygen sensor
This is an emission control system designed to reduce emissions and improve 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 airfuel ratio to provide optimum conditions for combustion and efficient reduction of the three
major pollutants (hydrocarbons, carbon monoxide and oxides of nitrogen (NOx) by a threeway catalytic converter.
Crankcase ventilation
The engine is provided with positive crankcase ventilation which prevents crankcase gases from being released into the
atmosphere. Instead, the crankcase gases are admitted to the intake manifold and cylinders.
Evaporative control system
The car is equipped with an evaporative control system which prevents gasoline vapor from being released into the
atmosphere.
The system consists of a fuel tank with filler pipe and cap, a rollover valve, a Fill Limit Vent Valve (FLVV), vapor
vent lines, a charcoal canister, a purge line, a purge control valve and engine connections .
In addition, there is a pressure sensor connected to the fuel tank and a filter-protected Canister Close Valve (CCV) on
the atmospheric side of the canister, for system diagnosis.
The gasoline vapor is channeled through the rollover valve and the FLVV via the vapor vent lines into the charcoal