Well the cable is not in the cluster, Unless the actual spring inside the gauge that will measure the spinning of the cable is messed up a new cluster won't fix the problem.
It's never happened to me so I have no answer, but the cable is a pain in the ass. I broke my connector off last time. Now I'm rolling without a speedo. Sucks balls.
I need to get a new cable.
anyhow good luck.
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2002 Subaru WRX
1988 Honda Civic Hatch