So I was gone over the Holiday and so I shut off all the water shut off valves. I could have just shut the 1 main value into the house, but there was someone in the basement.   
As I turned all the shut off valves on, I notice some water in one of the bathroom sinks, under the sink.  The shut off valves were the origional from 25 years ago so I replaced them all.     
Everything worked out ok except for 1 sink.  I put new shut off valves on, I put new SS hoses on. With the hose unhooked from the facuett and that end into a bucket I turned the shut of valve on and I get lots of good water pressure from both the hot and cold.   
After I hooked the hoses to the facuett, I checked for leaks and none to be found.   
But when I turn eithor or both the hot and/or cold water, all I get is a very very very small stream of water from the facuett.  I've never experienced this before,  I've had leaky faucets and eithor fix or replaced the fasuett, but how can a faucett go bad like this?