Hey, Can you chęci that valve next to n80 on active coal box. IT Has small hole on top, IT is correctly when there is vacuum pressure through hole while Engine running? When I turning off Engine and blow some air in hose IT also blowing from there. I can suck air from IT too without any resistance..
I would reset the error, which usually in the VW is something like "P044..". Fill up your car with gasoline or diesel and make sure the cap is fitted correcty. If the engine light comes back on quicly I would check for a cracked vapor canister, check the PCV/Purge Valve and last but not least check the lines running between the components. If you google "EVAP system" you will be able to find most components and where they should be in your car.
