I would recommend having your car checked over by a mechanic. Unfortunately it sounds like the previous owner did not take very good care of it.

 

The whistling is probably the intake. Manufacturers spend a lot of time on the intake/airbox combos so they don't whistle. We throw it all out and put a straight smooth pipe with an open filter on there. No sound dampening at all and its smooth inside and subject to howling.

If it changes pitches with the accelerator its intake whistle/howl.

 

ah thank you.. ya just think the sound would be coming more from the left than the right side, since the intake cone is more to the left.

 

If it is the intake then it would be coming more from the left - however, as others have noted it couldn't hurt to take the car to a mechanic to have to her checked over. That is good practice in general when you get a used car and the pitch black color of the old filter implies that the old owner didn't keep up with the maintenance - odds are you may need to fluids changed out as well.