Evaporative Emissions System: Description and Operation

Evaporative Emission Control System:

PURPOSE/OPERATION
The Evaporative Emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The system consists of the following components:

Vacuum Pump Gauge:

Vacuum Pressure Gauge / Except Sedan-Coupe EX Serial # F22B1-21xxxxx:

A. Evaporative Emission (EVAP) Control Canister.
An EVAP Control Canister is used for the temporary storage of fuel vapor until the fuel vapor can be purged from the EVAP Control Canister into the Engine and burned.

Vacuum Pressure Gauge / Sedan-Coupe EX Serial # F22B1-21xxxxx:

EVAP Control Solenoid Valve / View From Wire Side:

B. Vapor Purge Control System.
EVAP Control Canister purging is accomplished by drawing fresh air through the EVAP Control Canister and into a Port on the Throttle Body. The Purging Vacuum is controlled by the EVAP Purge Control Solenoid Valve.

Engine Coolant Temperature above 75°C (167°F) / Sedan - Coupe EX, Engine F22B1, 50°C (122°F) --> EVAP Purge Control Solenoid Valve on after starting Engine.

C. Fuel Tank Vapor Control System.
When fuel vapor pressure in the Fuel Tank is higher than the set value of the EVAP Two Way Valve, the Valve opens and regulates the flow of fuel vapor to the EVAP Control Canister.