FS 86 4kq Ottawa, Ontario, now 86 4kcsq gas mileage,& trip computers

[Marc Swanson]

> > I would rather just get the *outside temp* on the computer, I can
> > calculate economy at each fill up.  Any ideas?
>
> What happens if you connect the ECU to a thermistor instead of the
> intake sensor?


Well that's the general idea, but theres a few more issues to take into
account.

The input for the mileage reading takes data from the DPR and the
potentiometer (see the section in bentley about fixing the trip computer).
The trick is to take the wire going to the computer for each of these and
replace one of them with either some kind of clock signal or constant value
(my guess is that the DPR might have to be mimicked by a clock/pulse of some
kind) and then instead of whatever the linear input is, put the thermometer
across that.  But just when that started sounding easy you have to take into
account the fact that you might be causing the digits to go up and down..
but not neccesarily at the right scale or shift.  For that you'd have to put
in an op-amp and a resistor to put a gain and a scale on the input value
respectively.


There's GOTTA be an easier way than this... maybe an LCD that's just the
right size to replace the stock unit with one that's driven by a plain old
thermometer circuit?




-Marc-


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+Marc Swanson                          +
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+87 4kcstq                             +
+85 4ksq  "the spare"                  +
+87 5ktq   donor (Parting out)         +
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