Honda Repair: 92 accord speed sensor, rudimentary tools, speed sensor

Question
Hi Chris -

my Speed sensor on my 92 accord LX has been problematic for
over a year, with the speedometer jumping around and the S
light blinking and the check engine always on...but its been
pretty benign until recently, when if the speed sensor isn't
working, the transmission won't shift reliably.  if i'm in D4 or D3,
it'll stay in first and then at around 20 mph will go to neutral; i
can manually shift it to 1 or 2, but if i'm on the highway going
60 and the speed sensor bails again then i'm effectively in
neutral.  
When the speed sensor is working, everything shifts beautifully.

questions: do you think is this a problem beyond the speed
sensor?  my mechanic looked at the sensor and it seemed fine to
him; could it be just a loose cable?  how much should a new
(aftermarket) sensor cost?  and where exactly is it and how do i get to
it - can i replace it myself with a few rudimentary tools and a good
mindset?

thanks much in advance,
Roey

Answer
If the speed sensor is working properly I would definately check the cables that trigger the sport shift, if you do the diagnostic test with the check engine light and gave me the code that would help also. If it does come down to the speed sensor it is very simple to replace all you would basically need is a couple of wrenches and plyers.