Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

- EVAP control system pressure sensor - EVAP canister purge volume control solenoid valve (The valve is stuck open.) - EVAP canister vent control valve - EVAP canister - Hoses (Hoses are connected incorrectly or clogged.)

When Detected

The canister purge flow is detected during the specified driving conditions, even when EVAP canister purge volume control solenoid valve is completely closed.

Description

This system controls flow rate of fuel vapor from the EVAP canister. The opening of the vapor by-pass passage in the EVAP canister purge volume control solenoid valve changes to control the flow rate. The EVAP canister purge volume control solenoid valve repeats ON/OFF operation according to the signal sent from the Engine Control Module (ECM). The opening of the valve varies for optimum engine control. The optimum value stored in the ECM is determined by considering various engine conditions. When the engine is operating, the flow rate of fuel vapor from the EVAP canister is regulated as the air flow changes.