i wish it was that easy lol
but hey... try it... who knows it might be your problem
isc is the idle control valve, on the 1jz i believe it is at the back of the intake manifold closest to the firewall... has quite a large round unit bolted on by two bolts, inside that is the little disc which is a filter and black rubber o seal
pull em out, clean up the filter or see if you can possibly get a new one and just clean out where the filter sits
lmk if this does fix ur idle problem