On Board Refueling Vapor Recovery (ORVR)

DESCRIPTION
From the beginning of refueling, the fuel tank pressure goes up. When the pressure reaches the setting value of the refueling control valve (RCV) opening pressure, the RCV is opened. After RCV opens, the air and vapor inside the fuel tank go through refueling EVAP vapor cut valve, RCV and refueling vapor line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged during driving.
The RCV is always closed during driving and the evaporative emission control system is operated the same as conventional system.

WARNING:
When conducting inspections below, be sure to observe the following:
- Put a "CAUTION: INFLAMMABLE" sign in workshop.
- Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
- Be sure to furnish the workshop with a CO2 fire extinguisher.

CAUTION:
Before removing fuel line parts, carry out the following procedures:
a. Put drained fuel in an explosion-proof container and put lid on securely.
b. Release fuel pressure from fuel line. Refer to "Fuel Pressure Release".
c. Disconnect battery ground cable.
- Always replace O-ring when the fuel gauge retainer is removed.
- Do not kink or twist hose and tube when they are installed.
- Do not tighten hose and clamps excessively to avoid damaging hoses.
- After installation, run engine and check for fuel leaks at connection.

DIAGNOSTIC PROCEDURE




SYMPTOM: Fuel odor from EVAP canister is strong.




SYMPTOM: Cannot refuel/fuel odor from the fuel filler opening is strong while refueling.

COMP0NENT INSPECTION




Refueling Control Valve
Check Refueling Control valve as follows:
1. Check visually for cracks in the appearance.
2. Check air continuity between port A and B.
Blow air into the port A. Air should flow freely through port B.
3. Blow air into port C and check there is no leakage.
4. Apply pressure to both port A and C [20 kPa (150 mmHg, 5.91 mmHg)] and check there is no leakage from port B.
If NG, replace refueling valve.




Refueling EVAP Vapor Cut Valve
1. Remove fuel tank. Refer to "FUEL SYSTEM" in FE section. Drain fuel from the tank as follows:

With CONSULT
a. Remove fuel feed hose located on the fuel gauge retainer, and then connect a spare fuel hose to other side of the fuel container.
b. Drain fuel using "FUEL PUMP RELAY" in "ACTIVE TEST" mode with CONSULT.

Without CONSULT
a. Remove fuel gauge retainer.
b. Drain fuel from the tank using a hand pump into a fuel container.
2. Check valve head appearance visually for cracks.
3. Check refueling EVAP vapor cut valve close.
Blow air into the refueling EVAP vapor cut valve, and check that the air flows freely into the tank.
4. Check EVAP vapor cut valve open.
a. Connect vacuum pump to cut valve.
b. Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
c. Put fuel filler tank upside down.
d. Apply negative pressure [-13.3 kPa (-100 mmHg, -3.94 in Hg)] with fuel gauge retainer remaining open and check that the pressure is applicable.
If NG, replace refueling EVAP vapor cut valve with fuel tank.




One-way Fuel Valve
1. Drain fuel from the tank.
Refer to "COMPONENT INSPECTION" of refueling EVAP vapor cut valve.
2. Remove fuel filler tube and hose.
3. Check one-way fuel valve for operation.
When a stick is inserted, the valve should open, when removing stick it should close.
Do not drop any material into the tank.
If NG, replace one-way fuel valve with fuel tank.