98 2.0 atx, 97000 miles. heater works in all correct positions. Perhaps next week will get it scanned at autozone to check that. No cel light. I really think it might be the tranny. For a more exact sound, crack your window just a tad at about fifty mph to get that high pitch noise. Kinda sounds like that but no where as loud, if you talk while it happens you can't hear it.