coolant flowing between iac and isc ?

[fixkick]

all 3 are air valves
DP is cold start extra air for 3 to 30 seconds, heard every start up
the IAC is thermal air cold start idle air, 1500 to 2000 rpm, i know for fact it opens even more, at -10C, (i ran out of cold air there?) closes at 150F. all do.
the ISC is the hot air valve, that controls idle speeds at 800 rpm, this is just an air valve that the ecu modulates to get idle speed correct. (800 or 1000)

The ECU uses the ISC for many other reasons. , fast idle mode (1000 rpm) and cut throttle it opens to prevent passenger neck snap , discomforts.
they all work together, at all times, the ECU is in charge of this at all times.
the iSC may open too, for cold starts adding more air. (the ecu knows this and add fuel based on known cranking air. and when started that too..
the 8v is nasty wet manifold system that dont run good cold, to cure that and pass smog, they run faster idles in the TBI , cold.
to get cold wet fuel to vaporize. and not puddle up.

yare not related physically but are in software.
the ECU, controls both but never the IAC,
the ecu is hard coded for IAC thermal actions (tables), if it it messes up, so does the ECU.
case in point my iAC stuck open hot. *(a bad IAC)
the engine screams hot. like 2500 RPM or more.
the ECU can not lower it, with ISC action. so screams or screams and hunts as the ECU goes, nuts.

if engine idles at 800 rpm hot.its good.
if engine rpm does not drop, with head lights and blower fan on high same time. then ISC is working
if measured duty cycle is 50% hot, accessories off, then the ISC is happy. if not calibrate it.