Need a little Idle help

[stryker g8gt]

So about 3-4 months ago my car at idle starts flucuating RPMs by a couple hundred, then several hundred. got worse and worse over time. My Tuner played with Idle metrics for 2 hours. (I don't know a damn thing about this stuff) he got it a little better, but like he said the computer would not have changed unless something had changed/added tothe engine. So nothing had changed, no new mods, etc... Anyhow I have replaced the MAS Air Flow, plugs, plug wires (I found two that were coroded green and broke) This seemed to help now I only have a couple hundred at best rpm flucuation. but yesterday it went real sparatic and then died. Today it is oaky with just a little movement. I also grabed some propane and went around all the vaccuum hoses i could find, injectors, intake, throttle body and had no affect.... so i do not think I have any vaccuum leaks......... Next I wam looking at Up stream O2 sensors.. they due have 90k on them but no codes. And they seem to be trimming up and down on my guage. Of course the downs tream O2 are not there so they show a pretty steady .45 with no movement. But then agian I do not jack about this stuff........l;o

Any suggestions?

Between this and all the freaking Suspension noise I have recently, I am thinking trade in time. BCR coilovers have less then 18k on them and every corner sqeaks and squishes when going over bumps slowly with each tire....... sounds like I am driving an F150 with 250k miles on it