A rapid turn signal indicates a turn signal bulb is out.
Left ones fail first because we spend more time sitting at
lights wating to turn left (unless you are in the UK where I
assume the right one fails more often).

1998 model years had some issues with bulbs -- there was even
a recall to fit a new turn signal socket.

You might post a follow-up indicating your exact model and year
since that might help if anyone else has more specific info.