>  Anyone have an idea why my 81 will idle fine for the first few
> minutes, and then won't idle at all after that?  Also when I disconnect
> the head temp sender next to #3 it won't even start.

The thermo time switch sounds like one possibility, or a bad head temp
sender (which could be leaning the mixture out too much once the engine
warms up). There are other possibilities as well. But one thing I can tell
you for sure is that the engine will never start if you disconnect the temp
sender, because you are breaking a ground.  If you disconnect it, you must
ground out the wire to it.  This will fool the ECU into thinking the engine
is cold all the time.

- Ron Salmon
  The Bus Depot
  http://www.busdepot.com