Whisk Vinegar Bbq sauce ingredients together, set aside.
Rub bbq rub over pork pieces, making sure all pieces are fully covered. Place pork in Instant Pot and pour 1 ½ cups of vinegar bbq sauce and liquid smoke in insert. Cover and cook on high pressure for 60 minutes.
After 60 minutes, allow Instant Pot to naturally release for 10-15 minutes. Quick release remaining pressure.
Remove pork pieces from Instant Pot and shred. Drizzle with remaining vinegar bbq sauce when serving. Enjoy :)