Stupid question: Would having my O2 sensor not plugged in make my car run this way. I just found out the guy who had the car before me ran the main wire from the O2 sensor to AF ratio tool only to NOT CONTINUE ROUTING IT TO THE COMPUTER. I don't have time to take the stupid thing off yet but I can see that it has no possible way to go back to the computer so I'll let everybody know what happens when I finally get it to the computer, XD.

 

my o2 sensor was not plugged in for about 2 months, when i did plug it in it changed nothing. i belive(not 100% sure) its just for cruseing situations, so you may just get a little better MPG.