Volvo XC70 Automobile User Manual


 
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Technical data
Catalytic converter
General
The purpose of the catalytic converter is to
purify exhaust gases. It is located in the flow
of exhaust gasses close to the engine so that
it quickly reaches operating temperature.
The catalytic converter consists of a monolith
(ceramic or metal) with channels. The
channel walls are lined with platinum/
rhodium/palladium. These metals act as
catalysts, i.e. they participate in and accel-
erate a chemical reaction without being used
up themselves.
Lambda-sond
TM
oxygen sensor
The Lambda-sond is part of a control system
intended to reduce emissions and improve
fuel economy.
An oxygen sensor monitors the oxygen
content of the exhaust gases leaving the
engine. This value is fed into an electronic
system that continuously controls the
injectors. The ratio of air to fuel is continu-
ously adjusted. These adjustments create
optimal conditions for efficient combustion,
and together with the three-way catalytic
converter reduce harmful emissions (hydro-
carbons, carbon monoxide and nitrous
oxides).