Lilo & Stitch: The Series (2003)

S1E38 Bad Stitch

This episode has no experiments involved. Stitch's mischief is causing significant trouble for Nani, who is struggling to manage their financial responsibilities. If Stitch doesn’t change his ways, they may have to find him a new home. To assist with the bills, Stitch confesses to being an alien and seeks a scientist who might pay him for an examination. Unfortunately, he encounters Hamsterviel, who manipulates Stitch and restores his former chaotic programming, putting Nani's efforts in jeopardy.