94 SC engine surging - O2 replaced

I have 1994 SC2 experiencing major surging problems. This started about 9 months ago and at that time I replaced the 02 sensor and, because the check engine and low fluent lights were coming on as well as it was running hot, the temperatures sensors. From what I have read, these are the main reasons for the engine surging. It was better for a time period and has now resumed the surging. It is most noticeable when idling or at low speeds. I have friends that are mechanics and can do most work; they are not familiar with Saturns though and can't guarantee their diagnosis. I would like to avoid bringing it into the shop for this, as I am hoping to sell the car within the next couple of months and don't want to pump anymore money into it. Does anyone have any suggestions?

Idle air control valve