Refueling Vapor Recovery System: Testing and Inspection
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
System Description
From the beginning of refueling, the air and vapor inside the fuel tank go through refueling EVAP vapor cut valve and EVAP/ORVR 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.
WARNING:
When conducting inspections below, be sure to observe the following:
- Put a "CAUTION: FLAMMABLE" 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 fire extinguisher.
CAUTION:
- Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-proof container and put lid on securely.
- Release fuel pressure from fuel line. Testing and Inspection.
- Disconnect negative battery 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.
- Do not attempt to top off the fuel tank after the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray and possibly a fire.
Diagnosis Procedure
SYMPTOM: FUEL ODOR FROM EVAP CANISTER IS STRONG.
1. CHECK EVAP CANISTER
1.Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached. Exploded View.
2.Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
The weight should be less than 1.9 kg (4.2 lb).
OK or NG
OK- GO TO 2.
NG- GO TO 3.
2. CHECK IF EVAP CANISTER SATURATED WITH WATER
Does water drain from the EVAP canister?
Yes or No
Yes- GO TO 3.
No- GO TO 6.
3. REPLACE EVAP CANISTER
Replace EVAP canister with a new one. Exploded View.
- GO TO 4.
4. CHECK DRAIN FILTER
.
OK or NG
OK- GO TO 5.
NG- Replace drain filter. Exploded View.
5. DETECT MALFUNCTIONING PART
Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
- Repair or replace EVAP hose.
6. CHECK REFUELING EVAP VAPOR CUT VALVE
.
OK or NG
OK-INSPECTION END
NG- Replace refueling EVAP vapor cut valve with fuel tank. Component.
SYMPTOM: CANNOT REFUEL/FUEL ODOR FROM THE FUEL FILLER OPENING IS STRONG
WHILE REFUELING.
1. CHECK EVAP CANISTER
1.Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached. Exploded View.
2.Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
The weight should be less than 1.9 kg (4.2 lb).
OK or NG
OK- GO TO 2.
NG- GO TO 3.
2. CHECK IF EVAP CANISTER SATURATED WITH WATER
Does water drain from the EVAP canister?
Yes or No
Yes- GO TO 3.
No- GO TO 5.
3. REPLACE EVAP CANISTER
Replace EVAP canister with a new one. Exploded View.
- GO TO 4.
4. CHECK DRAIN FILTER
.
OK or NG
OK- GO TO 5.
NG- Replace drain filter. Exploded View.
5. DETECT MALFUNCTIONING PART
Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
- Repair or replace EVAP hose.
6. CHECK VENT HOSES AND VENT TUBES
Check hoses and tubes between EVAP canister and refueling EVAP vapor cut valve for clogging, kink, looseness and improper connection.
OK or NG
OK- GO TO 7.
NG- Repair or replace hoses and tubes.
7. CHECK FILLER NECK TUBE
Check recirculation line for clogging, dents and cracks.
OK or NG
OK- GO TO 8.
NG- Replace filler neck tube.
8. CHECK REFUELING EVAP VAPOR CUT VALVE
.
OK or NG
OK- GO TO 9.
NG- Replace refueling EVAP vapor cut valve with fuel tank. Component.
9. CHECK FUEL FILLER TUBE
Check filler neck tube and hose connected to the fuel tank for clogging, dents and cracks.
OK or NG
OK- GO TO 10.
NG- Replace fuel filler tube.
10. CHECK ONE-WAY FUEL VALVE-I
Check one-way valve for clogging.
OK or NG
OK- GO TO 11.
NG- Repair or replace one-way fuel valve with fuel tank. Component.
11. CHECK ONE-WAY FUEL VALVE-II
1.Make sure that fuel is drained from the tank.
2.Remove fuel filler tube and hose. Component.
3.Check one-way fuel valve for operation as follows.
When a stick is inserted, the valve should open, when removing stick it should close.
Do not drop any material into the tank.
OK or NG
OK-INSPECTION END
NG- Replace fuel filler tube or replace one-way fuel valve with fuel tank. Component.
Component Inspection
REFUELING EVAP VAPOR CUT VALVE
With CONSULT
1.Remove fuel tank. Removal and Installation.
2.Drain fuel from the tank as follows:
a.Remove fuel feed hose located on the fuel gauge retainer.
b.Connect a spare fuel hose, one side to fuel gauge retainer where the hose was removed and the other side to a fuel container.
c.Drain fuel using "FUEL PUMP RELAY" in "ACTIVE TEST" mode with CONSULT.
3.Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that the air flows freely into the tank.
4.Check refueling EVAP vapor cut valve for being stuck to open as follows.
a.Connect vacuum pump to hose end.
b.Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
c.Put fuel tank upside down.
d.Apply vacuum pressure to hose end [13.3 kPa (-100 mmHg, 3.94 inHg)] with fuel gauge retainer remaining open and check that the pressure is applicable.
Without CONSULT
1.Remove fuel tank. Removal and Installation.
2.Drain fuel from the tank as follows:
a.Remove fuel gauge retainer.
b.Drain fuel from the tank using a handy pump into a fuel container.
3.Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that the air flows freely into the tank.
4.Check refueling EVAP vapor cut valve for being stuck to open as follows.
a.Connect vacuum pump to hose end.
b.Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
c.Put fuel tank upside down.
d.Apply vacuum pressure to hose end [13.3 kPa (-100 mmHg, 3.94 inHg)] with fuel gauge retainer remaining open and check that the pressure is applicable.
DRAIN FILTER
1.Check visually for insect nests in the drain filter air inlet.
2.Check visually for cracks or flaws in the appearance.
3.Check visually for cracks or flaws in the hose.
4.Blow air into port A and check that it flows freely out of port B.
5.Block port B.
6.Blow air into port A and check that there is no leakage.
7.If NG, replace drain filter. Component.