fwiw,
if I suspect Temsor II ..
which I sure would on an 84 waterboxer vanagon
( or conenctions to it ! )
I would pull out my ohm meter and measure the reistance and compare that
to the chart in Bentley.

that is there standard test there too I believe..
measure resistance of Temp Sensor II ..right there onthe thermostat
housing , or near it ..
two wire connector there.
Be *real sure* it's getting a good connections. That connector gets old
and can be dodgy.

scott
turbovans

On 3/9/2013 4:33 PM, David Beierl wrote:
> At 06:40 PM 3/9/2013, john schaper wrote:
>> and can't figure out what part could be bad to even replace. Not
>> that I have ill will toward fellow vanagonites, but I hope someone
>> else has had this problem and can make suggestions.
>
> I'd be really interested to know what voltage the ECU was seeing on
> the Temp-II input (engine internal temp).  If you check before the
> day warms up after an overnight sit it ought to be very similar to
> the Temp-I input (AFM air temp).  If it's considerably lower the ECU
> would have the false impression of a warm engine.  That could be the
> result of a shorted sender, but a poor connection to the internal
> pull-up resistor inside the ECU would perhaps be a more likely cause.
>
> This could be one of those times when a trial swap of a known-good
> ECU could come in very handy.
>
> Yours,
> David
>