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

    Paul,
Thanks for the speedy reply to my query.  I was hoping you would have some thoughts about how to be sure it is the TPS causing the high idle rpm.  Is there a way to tell without having to take it to a dealer? Thanks again.  And I will look for you in the Lincoln tent at Sun 'n Fun.
Gerry Hanscom
        

No I don't. Could be a lot of things.

Could be a block temp sensor telling the computer the engine is cold so
the computer idles the engine faster but not 3000 RPM :)

I think the 1991 may have some built in diagnostics.
Download the shop manual from here.

http://foxed.ca/index.php?page=rx7manual

Paul Lamar