|Although your manager is not responding to your email, he is sending you a message, and it is either about him or about you. Look honestly at the email you have been sending. If your messages have been rambling, vague, or unfocused, then your manager's lack of response may be telling you to tighten this up. |
If your messages are on-target, then your manager is off-base. For example, his behavior might be a power play, and he wants you to see that he can answer you whenever he pleases, if he answers you at all. It is also possible that your manager is grossly unorganized and cannot get his managerial act together and get back to you. Or, he might lack the competence to give you a reasonable response. At the same time, perhaps he merely wants you to make some decisions for yourself, but if that is he message, he should convey directly to you.
The next time he ignores your email, you should either pick up the phone and call him, or pick yourself up and visit him. If you let this problem continue, you are going to fall further out of communication with him, and you are likely to fall further out of favor with him as well.