Honda Acura NSX 1991 Service Manual page 311

Description
controls
The evaporative are designed to minimize the amount of fuel vapor escaping to the atmosphere. The system consists of
the following components:
A. Charcoal Canister
A canister for the temporary storage of fuel vapor until the fuel vapor can be purged from the canister into the engine and
burned.
B. Vapor Purge Control System
Canister purging is accomplished by drawing fresh air through the canister and into a port on the throttle body. The
purging vacuum is controlled by the purge control diaphragm valve and the purge cut-off solenoid valve.
C . Fuel Tank Vapor Control System
When fuel vapor pressure in the fuel tank is higher than the set value of the two-way valve, the valve opens and regulates
the flow of fuel vapor to the canister.
PURGE CUT-OFF SOLENOID VALVE OFF AFTER START-
ING ENGINE
COOLANT TEMPERATURE ABOVE 7O"C (I 58OF)
II-135