2002 Saturn SL1 Jumps into reverse

Unfornately there's no easy answer to ur question u could have low line pressure in ur transmission a bad 2nd gear piston seal leaking a bad reverse servo piston seal or a loose input shaft nut. Without testing the transmission and seeing it it's impossible to tell. For ur yr and model though I would suspect the most likely cause for the delayed reverse would be a loose input shaft nut. Ur best bet would be to have a professionial look at. Let me know what u find.