[twindman]

Madmax - I think it was my 2006 that had the valve under the sink. I had a problem but don't remember what !!! I think it wouldn't flush. My valve was just a plastic type fitting that was threaded together, so I just unscrewed it. Inside was a marble thing that plugged the pipe when pressure came the back way. I just removed the marble and all was well. I could use an external back flow device to accomplish the same thing.