How to Fix low compression?

18 year old Saturn, chances are very high that the engine is just worn out, they were not the best even when they were in production. You can do a dry then wet compression test if your wondering if it rings or valves. But it sounds like it ready for the scrap heap.

This is a classic symptom of a jumped timing chain or belt. If you have a timing belt it's probably broken. Either way before you put any money into it see if you have an interference engine. If you do, the pistons have surely slammed into the valves when the timing chain jumped or the timing belt broke and the engine is done. Hope that helps! Jim