I came across this while searching online, the guy had ssold a van with
"New temp sensor and custom modifying circuit to keep van running
> cooler"
I tracked him down and this was his response
".I can give you the basics, but don't remember much beyond that.
Basically the temp sensor is a resistor that has more and more
resistance the hotter it gets.
So to make the engine run cooler, I put resistance in line with the
temp sensor to make the engine think it was hotter than it was, and
thus try to run cooler (via making the mixture richer, if I remember
right)..
I used Radio shack resistors (not sure if radio shack sells resistors
anymore), so I had to attach a longer wires so the resistors would be
on the inside of the van (otherwise they'd probably overheat.  I
connected two series of two parallel circuits, but can't remember
what the end resistance was that I added.

I did two in series and two in parallel because I didn't trust the
quality of the resistors...  Needed two in series in case one failed
as a closed circuit, and two in parallel in case one failed open.."

Any one heard of this??