If your 2013 personal return was extended then the final due date is October 15, 2014. Even if you cannot pay, filing by the extension still saves considerable penalties. If you owe and file after the deadline, the penalties and interest add up quickly.
If you are due a refund and do not file timely, you may never get your refund. You only have three years (in most cases) to request a refund. Once the time is up, the government keeps your money.
We need the rest of your information by September 30th to have a good chance of being finished before the deadline.