I bought one of those kits too. The dork only sent me instructions on what to buy,
but i figured it out, actually me and my buddy did. All you have to do is go to radio shack and tell the cashier your looking for resistors. They're extremely cheap.
You can buy like 5 for a buck, those are the ones i bought. Anyway, the IAT sensor is located to the right of the Hood
latch and if you are standing above it, it plugs into the plugs in towards the front of the car. What you do is unplug it, take a resistor and bend it into a u-shape, and plug it into the IAT sensor. Then the other half you originally unplugged, just take a piece of zip tie and tie somewher so it doesn't get caught up somewhere, and thats it. I wasn't too sure about the whole thing, but you can actually feel the difference. My friend did it to his Tacoma, which has an Intake
and exhaust, he his car flys now compared to what it did before.
My celica is all stock, and that tiny little resistor gave it a little more sac than it had. Hope this helps guys, later.