Chuck just looking at the idle problems. First the facts. The throttle butterfly should be fully closed, you should not adjust the stop screw to make it idle. The Idle Air Control works all the time, it provides the idle speed all the time, adjusting up and down to maintain the idle speed. When you open the throttle to rev the engine, the IAC valve opens fully, when you let the throttle close, the IAC valve will then close down, till the engine speed settles down to the the correct idle speed.
The Auxiliary Air Control has an electrical heated element that is turned on when you turn the ign on, it heats the bi metal spring to close it, over time. So if you pull the pipe to the AACV before you turn the key on, you should be able to blow through it. Turn the key on, and the valve will take about 1 minute to close.
If you are having idle speed problems, it could be caused by an vacuum leak, on the engine side of the throttle butterfly or, it is the Idle Air Control valve sticking, from gunk,that accumulates down there.
The heating problem. As you say the temp drops immediately, you turn on the heater, and goes back up when you turn the heater off. This is not likely to be the actually water temp, that is rising and falling, water doesn't gain and drop temp that fast. It would seem that the temp sensor, is sensing hot water, then no water. Check that the radiator is actually full, and there is no air in the system.
No idea on the last problem mate.
Harvey.
