I filed my extension on turbo tax -- I now need my form 4686 how do i get it?

it's 4868 so you may have been looking for the wrong form

anyway

1. Sign in to your TurboTax account and open (or continue) your return.
2. Select Tax Tools, then Print Center from the menu.
3. Choose Print, save, or preview this year's return, and follow any additional instructions.

you should be able to select only the extension for printing.