Evaporative Emission Controls
Description
The evaporative controls 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.
(cont'd)
PURGE CUT-OFF SOLENOID VALVE OFF AFTER START-
ING ENGINE
COOLANT TEMPERATURE ABOVE 70°C (1 58°F)ProCarManuals.com
Radiator and Condenser Fan Controls
Description
Fan control system:
The cooling fan system is comprised of radiator fan, condenser fan (left, right), engine compartment fan, radiator fan
low relay, radiator fan high relay, condenser fan relay, engine room fan relay, radiator fan resistor, coolant temperature
sensor, A/C pressure switch, cooling fan control unit, climate control unit, and PGM-FI ECU.
The fan control unit controls the operation of the radiator fan and condenser fan.
It uses inputs from the coolant temperature sensor and A/C pressure switch (A and B) on the A/C system to determine
when the fans should run and at what speed.
Additionally, the temperature switch shuts down the A/C system if the coolant temperature exceeds 130°C (266°F).
If the pressure in the A/C system is higher than normal, pressure switch A closes and the fans will run at high speed only.
See the A/C section for description and specification of that funciton.
Fans operating condition:ProCarManuals.com
