I just found a script to programatically delete a field collection to a specific node :
<?php
$node = node_load(1);
$field_collection_item_value = $node->field_page_collection1[LANGUAGE_NONE][0]['value']; // Take field collection item value.
entity_delete_multiple('field_collection_item', array($field_collection_item_value)); // Delete field collection item.
?>
Unfortunately as i see it , it only delete first field collection, I need to select which one i want to delete.
Here is my structure :
Multiple field collection who have : a reference to another node and two selects
I have the reference nid in the url so I can use it, but I don't have any idea how to select the right field collection with that.
Thanks