Bathroom Sink

[homeguy]

Our bathroom sink doesn\\\'t drain the water.

I\\\'ve used all the methods to verfiy if there\\\'s a clog (ie. baking soda/vingear, plunger,snake, nothing in trap, etc)

I think there\\\'s a vent(air)problem since when I run water with a hose directly into the pipe in the wall, there\\\'s no backup and the water can be heard draining into the main pipe. All other sinks & tubs run smooth in the rooms.

Where does it get it\\\'s air to drain the water ??

Thanks

[ChrisR]

DO you mean that it doesn't drain, or that it does but it's slow?
If it's slow, what's the diameter of the pipe and its length and gradient? I doubt venting has much to do with it if it's fairly short before getting to a large pipe or open hopper/gully.