Some times when my 2000 maxima is in park in idle instead of steady idle it is going from 1000 1500 rpm or from 1500 to 2000. What sensor is causing this? Any ideas? You can shut down and restart and its fine.

I ordered a new idle sensor and I dismantled the throttle bottle. Tore it all down and soaked in cleaner to get all that crud out (when I soaked it it was the bare metal part only no rubber or electronics in it). Took forever! Anyways new sensor installed and no issues now or at least it has not shown up again. I also installed 6 new coils from AM-autoparts.com
http://www.am-Autoparts.com/cart.html

Only 95 for all six coils I thought why not. Lets just say SHE WILL LIGHT THE TIRES NOW! Holy cow I had no idea how badly it was running went ahead and did the knock sensor the cam position sensor for all the codes I had. I was not happy where the knock sensor was dear lord as I just had that off few months back for the valve cover grrr oh well I should have done it then.

Im thinking at 158000 and no idea on the cats Im going to toss the whole exhaust system and cats for a new stuff seems I have some fumes and its not buring oil or leaking stuff. So I think thats the culprit.