is it NOT a good thing when family doctor and auto mechanic give the same non-answer.

several times i went to a doctor and ER for serious pain over a period of 10 years. it was so bad i had to go on disability for several months. each new doctor gave me an... i cant find anything wrong answer. now having a persistent check engine light on my 23 year old car, i took it in to dealership for a checkup and see if the cause of the code could be found and cleared. after three hours i got the same response...i dont know what is causing the problem. it could any of fifty minor things. since it runs so well and continues to get good fuel economy i will continue driving it until one of us dies.