My first suggestion is to select a small number of important projects for which you need his guidance the most. Next, construct a series of questions that will likely give you the details you need to handle those items. Now divide the questions into two types: open queries that require more detailed answers (e.g., "What three things do you like best about my ideas for this project?") and closed questions that warrant "yes" or "no" responses. A mix of both types will increase the likelihood of his answering, if not at length, then at least in brief.

Once the questions are set, ask them in an email or in person, based on the approach you think will furnish better replies. By alternating between open and closed questions, you will have guided the conversation and elicited the feedback you need. Later, as you carry out those projects based on his direction, positively reinforce his increased communicativeness by thanking him for his input and leadership. Over time his persistent cloudiness should segue into clarity. E