Volvo 850GLT User Manual
Page 160
1993 Volvo 850 GLT
secondary combustion of residual hydrocarbons and carbon monoxide, resulting in lower emissions
levels in the exhaust gases.
A- roll over valve, B- vacuum valve, C- inlet
manifold, D- charcoal canister, E- fuel tank
Evaporative control system
The car is equipped with a gas evaporative control system, which prevents gasoline fumes from being
released into the atmosphere. The system is comprised of an expansion chamber in the fuel tank, a roll-
over valve on the cross member in front of the fuel tank and a charcoal canister with a built-in vacuum
valve under the left-front wheel housing.
The components are interconnected by hoses which channel fuel vapor from the gas tank to the charcoal
filter, where it is stored until the engine is started and then drawn into the engine's air intake system.
Crankcase ventilation
The engine is provided with positive crankcase ventilation which prevents crankcase gases from being
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