Make the dry rub by mixing all the ingredients for the rub in a small bowl.
Pat dry the ribs with a paper towel and remove the membranes if they still have them. To do this just flip the ribs face down and then slide the tip of a fork or knife to lift up the membrane. Then just pull it off with your hands or with a paper towel.
Season the ribs well with the dry rub on both sides.
Place the steam rack inside the Instant Pot. Add the water, apple cider vinegar, and liquid smoke (if using). Then place the ribs in the pot wrapping them around to form a circle.
Set the lid to close and ensure that the switch is set to "Seal" or the vent is set to the "Sealing" position.
Press the button “Pressure Cook” and cook on “High Pressure” for 25 minutes.
Once it's done, allow the pot to release the pressure naturally for 15 minutes, then move the switch on the lid to “Vent” to release the rest of the pressure.
Remove the ribs from the Instant Pot, place them on a baking sheet covered with aluminum foil, and brush them with the BBQ sauce.
Broil the ribs for 2-3 minutes or until the BBQ sauce begins to caramelize. Serve with more sauce if you want.