i have a 1993 taurus and i seem to be loosing oil it, doesn't seem to be burning or leaking but i have to put a quart in every 600 miles i heard of a filter in the valve cover by the pcv valve hole. is this ture?

I am not familiar with such a filter. My Haynes manual does not mention it either.

A quart every 600 miles seems like a lot, even after 11 years. If there is no obvious visible leak then you must be burning it. If you are burning it I would think you should see the tell-tale blue exhaust smoke, especially under a hard acceleration.

Could be PCV valve...cheap try.
That is a lot of oil usage...but you may not necessarily see
smoke....I had a Saturn that went through that much oil...
and there was nothing visible...g'luck

Have you checked the spark plugs to see if you are burning oil?

The age of the car isn't as important as how many miles are on it and how has it been cared for. A worn engine will use some oil.