Need help with idel on a 97 gst

If anyone could help would be greatly appreciated. I have the idle set at 800rpms on my 97 gst but when idling it keeps jumping up to like 2000rpms and then goes back down and then up then down and so on. So if anyone knows any ways to maybe fix this please tell

Sounds like the ISC may be going out. I would pull the throttlebody off and clean it out good and then check the ISC to make sure its working properly. Also replace the spark plugs if haven't done lately.

Is this Check Engine Light on?

I pulled the throttlebody off and cleaned everything, and put new plugs and wires on and still doing it. It did have a check engine light on and i just checked it and it said that i need a new 02 sensore in #2 as the wire broke to the o2 sensore and also said miss fire in cylender 1.

Is it possiable for the nock sensore to be doing all this?