Yesterday while driving over to relatives home for Thanksgiving... our son and his family were following us down the highway in their Honda CRV. Later he quietly mentioned that he observed the Prius v5 exhaust tail pipe produce a puff of vapor... (as in a mild water puff backfire). It only happened one time. No noise was heard while driving. Only thought was probably the tail pipe accumulated enough water solution to be expelled as water solution vapor. Pruis v5 silently passes gas ?
