Prius v (lowercase v for Prius v) recall

After hearing about new Toyota recalls, we entered our vin of our 2012 v and there was a recall from 2012. It is Recall 161 revised 07.17,2012. *replace exhaust pipe gas control actuator. The dealer said it is a valve that is hooked to the water pump.... has anybody heard of this???
We are taking it in next Wed. for this, then the dealership just phoned today and bumped up the app from 1pm to 11am ...same day because they have never changed one and don't know how long it would take. I know we weren't the only v sold around here and they have never changed one???
The girl at the service desk said that the recall expires May 2015. This has me baffled.

 

Thanks Lee, now I understand what it is all about. This is the first I heard about it, as we did not get a letter.
Thanks

 

Well leaving in a couple hours to take it in for the recall, I hope it only takes a couple hours like Rude person's's did.