Yes, it is possible to overcook pork carnitas. Leaving the pork in the Instant Pot for too long can lead to overcooked and dry meat. Overcooking can cause the pork to become mushy and lose its desired texture. The meat may also become stringy or fall apart excessively, making it challenging to serve or enjoy. To avoid overcooking pork carnitas, it's essential to follow the recommended cooking times in your recipe closely.