Honey, I Shrunk the Rangers: Part 1 - S1-E16
Deliberate mistake: Monkey Bulk & Skull are driving Lt. Stone's car. From inside shots of the car, Monkey Bulk's head doesn't go above the headrest. From outside shots, we can see the guy who was driving the car - his head is way above the headrest, and he's wearing a frizzy fur costume (Monkey Bulk & Skull's fur is very fine).
Honey, I Shrunk the Rangers: Part 1 - S1-E16
Continuity mistake: The sign outside the Youth Centre changes in this episode, yet is back to normal in the next episode.
Answer: Scheduling problems with Hilary Shepard Turner meant that she was unable to reprise her role as Divatox from "Turbo: A Power Rangers Movie". Carol Hoyt was brought in as a replacement until the major cast change mid-season, when Hilary returned. Carol still played Dimitria, the Rangers' mentor.