i assume you have already tried to install it?
if you have... then your car surging will most likely be the isc leaking so basically intake manifold leak... runs rich as... attempts to stall due to fuel flooding
now you've got my memory banks going... its been a while since i did mine too lol
i believe this is how it goes
put isc inside manifold with mesh/filter facing out, gasket then on top of that, then install the isc assembly
anyone done one recently to confirm this? lol
here's a link to the online manual
http://www.cygnusx1.net/supra/librar...fi/FI_106.html