Air temp sensors

[dlawson@ball.com (Dave Lawson)]

Well, I have started driving the ur-quattro again. Thanks to some
tips from Mr. PDQSHIP, I dialed in the O2 frequency valve duty
cycle and the engine idle speed. Now it seems to run fine. Since
I am not using the 200 fuse box and FP relay, I connected the
knock sensor light output to an LED and momentary pushbutton
switch, which is mounted to an auxillary gauge panel. This device
allows me to download the ECU fault codes at the 'push of a button'.

In dumping the fault codes I come upon a 2322, air temperature
sensor. I installed the sensor from the original ur-quattro engine.
Measuring the resistance of the sensor it is 20.5 ohms, a correct
value based upong the quattro maintainance manual. But, the
Bentley says the 89 200 MC engine should have a value between
400-700 ohms. Lesson learned and passed on, the TQC air temp
sensor is not the correct one for the 5000/200 MC engines.

So I hit a local shop and pick up an air temp sensor from a mashed
87 5000 turbo. The wires are soldered on, so I snip them close to the
sensor tabs and head home. Resistance measures 500 ohms and
increases when hot air is applied. Great this guy works. Now I go
and try to remove the soldered on leads, no deal. With my puny
Radio Schlack soldering iron, they don't even begin to budge.
Bring the sensor to work, have one of the ace electrical fabricators
take a wack at it, with >700 degrees temp, the leads don't move.
I take it home, fire up the propane torch and apply flame. The plastic
around the leads begins to soften, but the soldered on tabs still don't
move. What bond have I encountered? Has Audi developed a new
way of joining two metals into one for maximum electrical conductivity
(possibly even better than a crimp connection)?

Let me know how you 'netsters unsolder these wires.
 -
Dave Lawson  dlawson@ball.com
Boulder, CO
83 ur-quattro, lhasa green and out roaming the streets of Boulder