Windshield Wiper/washer problems of the 1996 Chrysler Sebring

This problem has almost cost me and my passenger our lives. It is not something that is reproducable on demand, but I have witnesses on the happenings. It happens at different speeds, different timings, but the amount of rain seems to be a factor. I have tried several times to resolve this at the dealer but since it is not reproducable they will not fix it. I reported this before my warranty ran out. I can not be taking chances during the rain and snowy weather an having my wipers just stop working. Roads are dark, many have no shoulder to pull off on and highways now do not have shoulders either. Please help me with this issue and getting it resolved. No safety defect listed.