you are not supposed to overfill your tank...this will cause problems as you have ...
yes the tank has a very set computer controlled pressure /purge system so as to keep the tank at a slight vacuum....on shut down vapors get stored into the cannistor...If you overfill liquid gets sent to cannister this then causes problems like you have..it is not designed for liquid...this problem may go away with not over filling...as the vapor/liquid slowly gets purged from the charcoal...BUT it is written that if the cannister is filled with liquid it should be replaced..
the other components could also be damaged but hopefully not..