Lotus Evora Service Notes page 224

Lotus Service Notes
press button quickfit connector to join to the mid-positioned spigot on the canister marked 'TANK', within which
the port is extended to the far end of the charcoal bed. In this way, vapour from the fuel tank is cleansed of fuel
by the charcoal bed before being vented.
A second quickfit type connector is used on the purge pipe spigot positioned uppermost and marked
'PURGE', and which also communicates with the left hand end of the bed. The external pipe from this port
incorporates a service test connector before joining the purge solenoid valve mounted on the rear end of the
LH camshaft cover. The outlet pipe from this valve connects to the engine intake plenum just downstream of
the throttle valve. The solenoid valve is opened during certain engine running conditions in order to allow in-
take depression to draw fresh air through the vent pipe and charcoal bed, cleansing the charcoal of fuel before
consuming the resultant vapour in the normal combustion process. In this way, the charcoal is prepared for
further vapour absorption when the engine is stopped.
Control System
The canister purge valve is controlled by the engine management ECU, which keeps the valve closed
(unenergised) when the engine is cold or idling in order to protect the catalyst and maintain idle quality. At
normal running temperatures and engine speeds above idle, the ECU monitors other parameters and sensor
data and when appropriate conditions pertain, the ECU will apply a duty cycle to the valve in order to regulate
the amount of purging allowed, so as not to corrupt the smooth running of the engine.
Section LN
Page 9