My 87 Turbo just started this.... I was driving one night stopped for a minute stepped out of the car and heard this terrible knocking/rattling sound!! Brought her home and the next day jacked the car up after running with the valve covers off thinking it was in the head. Had the trusty stethoscope screwdriver and am unable to pin where the noise is coming from. So aside from a failing main bearing I am wondering since the noise sounds external around the bell housing or the worst case scenario main bearing lash in the back end of the engine. So my ? for any who know or have experienced the similar sound has your failing clutch/throwout bearing/ shift fork etc..... ever made any such noise??? It does not stop with the clutch engaged or disengaged it will slow with engine speed and decrees in acceleration. So I ask my trusty fellow Supra lovers for any advice once again. Its a JDM Sawp allready fixed a bad HG had the head machined and did not notice any unusual wear or debrees in the crank case when I had the pan off the engine. Did not touch the clutch 4500 rpm is what set it off.
