I owe taxes but I don't remember if I said to auto deduct from my checking account or not.....

[MollsBBU · Accepted solution]

If you did, the date of debit will default to April 18, 2017 unless you select a different date. You may locate this by reviewing your filed forms and worksheets. 

1. Sign in to TurboTax Online
2. On the white bar at the top, from the My TurboTax drop-down menu, select My Tax Timeline.
3. At the bottom of the 2016 year, there is a SOME THINGS YOU CAN DO section
   
4. Select Download all forms and worksheets
5. Next, select I need it for something else

After you download everything, find your Federal Information Worksheet (note you may find this worksheet several pages in). Please see the screenshot below "Federal Information Worksheet" so you can more easily recognize the heading of this form in your file.

On page 2 of the Federal Information Worksheet, you may find the account information in Section V. Please see the screenshot "Account Info for Debit" below for an example.

If you wish to change the date, please see  this answer  for steps to take.