Well the picture has become clearer. I went back to where I heard "something fall?" through the engine compartment at an intersection at the same time the HB came off. It was the crankshaft pulley bolt and washer (it was like frogger grabbing those those out of the road). Worse part is bolt was snapped off with only about 1/4in of threads remaining. Is it junk yard time? I do not have anywhere to start tearing this motor down and although the link provided earlier in this post does look like a solid fix, the motor already has 150K+ on it and has been using oil. Now the question is, has the oil just been leaking out the front cover where I noticed a pool of oil on the top of the skid plate? I don't know, anywhere near Indiana need a project Mitsu?