OK folks, problem solved -
I simply swapped out the PC board with another ZipZaps car (60-7014) that had a broken chassis... range is as it should be now, 35-45+ feet or so -
Dunno what could have possibly happened to the bad PC board, must simply be a defect. Drives me nutz with as little usage that the car had, and of course, it's not under warranty anymore <aarrgghh>.