I believe that was the code I had on my 96 and it was a leaky exhaust. It was on a bend and just old age rusted through. Try to find a shop that won't insist on changing out the catalyst, just custom make a new pipe section and weld it in.
Climb under and start listening and feeling for the leak, should be easy to find. Mine was under the heat shield:
Last edited by deanbrown; 06-09-11 at 11:08 PM.