coolant flowing between iac and isc ?

[fixkick]

id never change any starter
unless it fails the hot wire test.
1min tests. saves, what 3 hours labor? (in your case more, removing a donor starter)
i always assume something simple wrong, can be....!
even a weak battery. or the green death on battery cables.
or as on one car, (many) the Previous owner had a brain fart and put the battery neg lug, (end)
not under the top bolt of starter mount bolt. (used the frame or? some other wild wrong guess)
or he forgot to tighten it and is loose, and now cant pass 100 to 500 amps current. (a super simple error...)
if you have a volt meter all this is so easy..... vastly more easy than guessing. a $10 tool, all shops have.
if the volts are not 12.6v, stop. end bad day in snow.
the battery is dead, discharged.
next step, charge it, or jumper start car.. if engine starts the charging system then charges that dead battery, if the charge lamp is off.