Toyota Repair: CHECK ENGINE LIGHT KEEPS COMING ON, trip out of town, toyota sienna

Question
2003 TOYOTA SIENNA I HAVE HAD PROBLEMS WITH MY CHECK ENGINE LIGHT THAT KEEPS COMING ON . I HAVE HAD IT FIX AT LEAST TO 2 TIMES WITH DIFFERENT PARTS BEING REPLACED. ALL TO DO WITH THE EXHAUST SYSTEM. I AM NOW BRINGING BACK FOR THE 3RD TIME WITH CHECK ENGINE LIGHT ON AGAIN. THIS SEEMS TO HAPPEN AFTER I MAKE A TRIP OUT OF TOWN. THE LIGHT SEEM TO GO ON AFTER I'M BACK. MY CAR IS RUNNING FINE BUT I'M GETTING TIED OF BRING MY CAR IN FOR REPAIRS AND THE LIGHT STILL COMES ON.I HAVE 90,453 MILES ON MY CAR.

Answer
Hello, I understand your frustration but there are two things I need to know so I can help:
What are the diagnostic trouble codes in the computer at this time?
What EXACTLY did they replace already?
You can get this information from past repair order copies. If not you can get the trouble code numbers for me at most Autozone or similar autoparts stores, they will help you get them and please write them down or get a printout, then you can reply to me and we can go from there but I still need to know what they already replaced. I'm sure I can help you but I need this information.