V50 w646.book - ESD - Volvo

11 Specifications
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 a thin layer of platinum,
rhodium and palladium. These metals
act as catalysts, i.e. they participate in and
accelerate 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 continuously adjusted.
These adjustments create optimal conditions
for efficient combustion, and together
with the three-way catalytic converter reduce
harmful emissions (hydrocarbons, carbon
monoxide and nitrous oxides).
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