Engine starts, after not pushing the fuel pedal it goes off

Hello all,

I have a huge problem here, today after driving in the rain and dropping my wife at her sister's house the car started to behave really bad.

At first it didn't wanted to start so I check the battery and see if it needed to be replaced, it was just fine, so I tried again but this time also pushing the fuel pedal and the car started, good!!! However after releasing the pedal the engine went off, I tried several times and it seems to allways be the same.

I have an Octavia Classic 2003 gasoline 1.4lt.