O2 sensor & surging
 

Earlier this week I posted a question about a free-dangling wire in my engine compartment, which has been identified the O2 sensor.

http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/363275-whats-wire.html

I replugged it back together (the air pump isn't connected, BTW). However, I noticed a mild surging when driving at a steady throttle. Kind of like being on a large boat/ship, and feeling the swells of the ocean. Maybe not even noticeable to a passenger, but noticeable to me, with my foot on the accelerator. I unplugged the O2 sensor, and the surging went away.

So my question: why is this happening, and am I better off just running the car with the O2 sensor disconnected?

You need to have your CO adjusted... Someone unplugged it and turned the CO up to much. Buy a Gunson gas analyzer and do it yourself. I set mine to 3%with headers and no cat.