Refueling Control Valve: Testing and Inspection

Fuel Tank Vapor Control Valve Test

Special Tools Required
Vacuum pump/gauge, 0 - 30 in.Hg, Snap-on YA4000A or equivalent, commercially available

Float Test

1. Make sure the fuel tank is less than half full.
2. Remove the fuel fill cap to relieve the fuel tank pressure, then reinstall the cap.




3. Remove the fuel pipe cover. Disconnect the fuel tank vapor recirculation tube (A), and connect a commercially available vacuum pump/gauge, 0 - 30 in.Hg, to the hose.
4. Plug the fuel tank vapor recirculation pipe (B).
5. Apply vacuum to the fuel tank vapor recirculation tube(A).
- If the vacuum holds, replace the fuel tank vapor control valve.
- If the vacuum does not hold, the float is OK. Go to step 1 of the valve test.

Valve Test

1. Make sure the fuel tank is less than half full.
2. Remove the fuel fill cap.




3. Remove the fuel pipe cover. Disconnect the fuel tank vapor signal tube (A).




4. Disconnect the vacuum hoses (A) from the EVAP canister (B), and then plug the ports with plugs (C).
5. Disconnect the vacuum hose (D) from the EVAP canister vent shut valve (E), and connect a commercially available vacuum pump/gauge, 0 - 30 in.Hg, to the EVAP canister vent shut valve.
6. Pump the vacuum pump 80 times.
- If the vacuum holds, go to step 7.
- If the vacuum does not hold, go to step 9.




7. Connect a second vacuum pump/gauge to the fuel tank vapor signal tube (A).
8. Apply vacuum (1 pump) to the fuel tank vapor signal tube (A), then check the vacuum on the pump in step 6.
- If the vacuum holds, replace the fuel tank vapor control valve.
- If the vacuum is released, the fuel tank vapor control valve is OK.

9. Disconnect the fuel tank vapor quick disconnect from the EVAP canister, then plug the port on the canister. Reapply vacuum (80 pumps).
- If the vacuum holds, replace the fuel tank vapor control valve.
- If the vacuum does not hold, inspect the EVAP canister vent shut valve O-ring. If the O-ring is OK, replace the EVAP canister and repeat step 4.