After installing my headers I took my car for a test drive, my A/C was blowing warm air and after 15 minutes the temp guage was almost in the red. I checked and found my fans werent turning on.

I did a search and found that the passenger side o2 sensor is somehow related with the fan ground. I checked if anything was touching and everything looks fine. And the fans manually turn on when tested, so I know the fans dont have a problem.

Any ideas?

 

Make sure your headers didn't burn any wires.

 

the headers probably burned a wire or something, and im not trying to insult you or anything (i have done this several times) are you sure that you plugged everything back in?