KWHines: I was told at the April '95 Autocross at Black Hawk Farms Rockford IL that the clicking noise was an exhaust leak at the exhaust manifold. My St. Louis dealing confirmed this. My '87 5000CS TQ makes this noise intermittenly. Although slightly perturbing, I have noticed no performance or safety related problems. (I bet the greenies don't like the cat to be bypassed though!)