[s8loud]

It sounds like you're focusing more on what he does wrong than what he does right, although I can certainly understand how easy that is to do, cuz at 16, doing the right thing should be the rule, not the exception. However, given the situation, you could try some simple positive reinforcement, making a big deal out of the good that he does; that let's him know that you're paying attention to his efforts and, thus, that you care about him.

Also, you mentioned that you don't know what he wants. That suggests to me that you might not spend much (or enough) time with him, whether by choice or not. If at all possible, set aside some time for just the two of you. At 16, he may not be open to such a direct overture, so you may have to 'plan it' so that the two of you end up in situations where it's just the two of you together (and let things flow from there).

Whatever you decide, do your best not to do things that create distance between the two of you (like sending him out of the house), cuz that may indeed be the root cause of all this. You may have to seek out new ways of communicating with him as well as finding other methods of getting him to open up to you, cuz the "I don't know"s are often just an easy way to avoid confronting what it is he really wants, and it's up to you to either get it out of him or help him find it.

Good luck.