Toyota Repair: 1999 toyota corolla, toyota corolla, engine misfire

Question
My car was running fine then all at once I started out on the interstate at about 70 mph and it felt like I had a flat tire.  No flat tire, but it continued to slightly shake and my engine light went on and off continuously.  It felt like my car wanted to die out going 70 mph.  I do have a oil leak that is spueing oil on the belts and I thought it might have made the belts slip or maybe got oil on a fuze box or something.  It never died out and got me home but it was all of the sudden.

Answer
Since the check engine light turned on there may be an engine misfire, the first thing I would need is to find out if there are any diagnostic trouble codes in the engine control computer, you can get this information at no charge if you can get the car to an Autozone, Kragen or other large autoparts store, they will usually connect a diagnostic tool to the car and give you some code numbers, once you have them you can reply here and let me know those codes and I can tell you what the problem may be and a recommendation what should be done, avoid driving the car a lot while the engine light is flashing, it means the catalityc converter is overheating and can be damaged which is a very expensive repair.