it is usually on the block right in the middle of the cylinders, right below the headgasket line. being a fwd i-30, im going to think there's still only one sensor (i'm not sure if any came with 2), but chances are it's hidden away on the backside/firewall side. look on middle cylinder and it will be a big black plastic deal, round, with a bolt through it into the block and a wire loom heading to a connector usually. might be a toughie to find. changing it is a matter of connector and one bolt (usually 12mm IIRC) away. tell your gf to do it she has small hands lol.