Hi, Paul,
  I have a lead on a 1991 RX-7 (non turbo) that the owner says
  needs a throttle positioning sensor.  It idles at about 3000
  rpm.  I have called my local parts dealers and it appears that
  a replacement part is from $400 to $600.  List is about $900.
  How can I prove to myself it is in fact a TPS problem, and if
  it really is, do you or anyone else reading this, have a source
  that can save me any $$?  Do the race cars even use TPS's, and
  if not, can I get one they might otherwise throw away?
  Thanks for any help you can provide.
  Gerry Hanscom
  P.S.  I'm going to be at Sun 'n Fun.  Hope to see you there,
  but I would like to react on this RX-7 before then.  Thanks again.


  I might be at Sun N Fun. If so I plan to spend a lot of time in
  the Lincoln welding tent learning how to tig weld aluminum.

  TPS are simple devices. Basically just a potentiometer
  connected to the throttle shaft . I suggest looking on Ebay. A
  unit for a different kind of car with about the same power
  would work.

  Paul Lamar

Gerry...
If you want a new one, Rock Auto has one that's brand new for
$193...I've bought several parts from them in the past...
http://tinyurl.com/ae45qhr

Harley




I pretty much buy all my auto parts from RockAuto with the exception of
such items as exhaust pipes that cost a fortune to ship because they are
so large.  I get those items directly from my local Auto Zone.  I don't
have to pay any shipping that way.

 Mark LaPierre