Scheme 49
Carry out check for air leakage according to Check for air leaks in the intake system.
General information about the on-board refueling vapor recovery valve
The on-board refueling vapor recovery valve closes the tank nozzle when the tank is being filled to prevent overfilling. When the fuel tank is filled and is full the on-board refueling vapor recovery valve changes position and creates a back pressure which stops the filling automatically.
If the on-board refueling vapor recovery valve sticks the fuel tank will overfill and then the evaporative emission system (EVAP) canister fills up. When the evaporative emission system (EVAP) canister is filled with fuel too much fuel will enter the engine when the evaporative emission system (EVAP) valve opens. The engine cannot compensate for the large fuel flow and the engine will stop. This occurs when idling.
The clearest symptom that the on-board refueling vapor recovery valve is sticking is that the engine stalls when idling after filling with fuel. This usually occurs for a short period after filling the tank and then the symptom decreases quickly. It can also cause uneven idling.
The corrective action in event of the on-board refueling vapor recovery valve sticking is to replace the fuel tank.
Checking the on-board refueling vapor recovery valve
The on-board refueling vapor recovery valve itself cannot be checked.
The check is made of the volumetric efficiency of the evaporative emission system (EVAP) canister.
If the evaporative emission system (EVAP) canister is full it can indicate that the on-board refueling vapor recovery valve is sticking.
Checking the volumetric efficiency of the evaporative emission system (EVAP) canister
- Disconnect the hose from the fuel tank beside the evaporative emission system (EVAP) valve
- Pull the hose down level with the bottom of the engine
- Check if fuel comes out of hose.
If fuel comes from the hose it indicates that the evaporative emission system (EVAP) canister is over full.
Remedy as necessary.
Other information
- To replace the fuel tank, see «Replacing the fuel tank»(ref-440269-S13317846432011121400000).
- Continue Refer to «Information»(ref-440270-S39977625082011121400000)