So my cat i fear might be toast. Seem to have strange back pressure issues as if its clogged and going up hills sometimes now I smell the rotten eggs smell. 95 LS with 171k. Ran rich for awhile cause I had the wrong ecu in the car and didn't know it. That prolly brought the life down a bit. Think its toast? How well do aftermarket cats (high flow) work for emissions in washington. Next time I renew my tabs i'll have to get emissions done