So I finally got my engine back together, but when it's running, the fan never comes on and the temp gauge proceeds to max out. When I turn the A/C on, the passenger fan comes on no problem. When I disconnect the water pump temp sensor both fans go into default and come on. So, I know it's not a problem with my fans. My thought is that it is the one wire temp sensor on the passenger side head. Does it have to ground through the threads? I used teflon tape for the installation. Perhaps this is the reason why my fan is not coming on?