I have seen a few of those plastic T pieces fail and leave the owners on the road to get towed and into expenses.  
They are not expensive and need to be changed now, in my opinion.  The water cooled vans have two of them.  I always keep a few at my place for a quick change.  These are age related items, like the fuel lines.  The kind that we don't fix when they fail, but change when they are old.  
Bes wishes to all,
Zoltan