Last week I drove to my sister's house and my coolant temp light came on while en route. Checked fluids, made note of what needed topping off. Last night my service engine light popped on and stayed on when I started my car. I went out today, filled the coolant, checked the oil, etc. Engine has had vibrations and idling inconsistencies (idles between 800-1200 when in Park, changes when I turn AC on/off or any other power draw) since I bought the car roughly a month ago. I have no service records for the vehicle and not alot of cash on hand for major repairs so I'd really like to get the issues resolved before they become major. I'm a newbie to Saturn, have no clue what I've gotten myself into...any suggestions on steps to repair? I plan on taking it in to have the codes read, but to be honest, I'm a little nervous about driving the 20+ miles to town with the check engine light on.