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Hi, my 1995 ES300 will accelerate and the tachometer will jump up and down while driving. Could it be that the tranny is shot or could it be a sensor. My baby girl is driving this car and it scares me when she leaves in it. I had the tranny fluid changed but not flushed as I had requested of them. No metal shavings. What should I do next? Are the sensors hidden under the hood or easy to find.