what causes my gear transmission to go off on gear 3 or 4 on speed ? on 2002 Lexus ES300

once this happens I reduce speed and it returns to the low gear when i increase speed it goes off again am really troubled about this, i took it to run a scan with an error code reporting " gear speed sensor not found" could this be the problem ??

by in Nelsonia, VA on April 14, 2013
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1 answer
ANSWER by , April 14, 2013
take it to a tranny shop for diag