im in the middle of putting in a heated oxygen sensor and i've read many post about using the fuel pump relay for the 12v wire but i don't think i want to mess with that. who ever had my car before rigged up the fan so it comes on, and stays on, as soon as you start the car. im thinking of tapping into that wire. what do ya'll think? i know the heater for the o2 will stay on as long as the car is on but that won't hurt anything will it? i hardly ever take my car on long trips.