Strange one this, car is leaking fuel around the tank, but especially when the engine is running. When running if the fuel cap is removed fuel is ejected from the filler pipe, the leak is enough to lose about half a gallon in 5 miles when running. There is no sign of damage the fuel filter was changed about 1k back and isn't leaking. The engine is running silky smooth and not misfiring. Is there a vent to to the filler pipe, as also there is a vacuum froming in the tank due to the gurgling noise from the tank when removing the cap if engine not running.

Had the exact same thing on my leon years ago. Turned out the fuel supply, breath and return to tank pipework was mixed up.

Drivers side under the bonnet will be a charcol canister with 3 pipes connected at the top, check the order of these is correct.

Any idea what order they should be in?

Also read that the canister valve can stick anybody heard if this??

On the leon they were colour coded, will have a look in the morning on the octavia.

Cheers

Sorry for delay,

You can see where I mean behind header tank, hope this helps.

Blockage in pipe

Where filter is disconnect pipe for vent and run car with it venting to atmosphere and see if it does it then

If it doesn't then it either pipe to charcoal filter or charcoal canister valve closed

Problem solved pipe from charcoal filter and middle pipe wrong way round, been like this since Cambelt change in December, strange how it took this long to be an issue, must be down to a nearly empty fuel tank.

Thanks for the help.

Edited 15 April, 201313 yr by cyclesilly