ok so my car has this bad habbit of a rough idle, but not all the time just whenever it feels like it. so my question is what are the posibilitys?
First off, i replaced the iac not to long ago, that helped with some of the problems but i still got left with the shaky butt idle(mind you it can run smooth) the only things i can think of tho is MAF(which i just cleaned, helps but doesnt fix it)fuel filter which is new and didnt change a dam thing TPS? and maybe the crank sensor?
since its kinda a random idle problem i wouldnt think it could be a vaccum leak since i imagine that would be more consistant, i could be wrong tho. Any input would be great, as well as the easiest way to check.

 

Does it do it immediately on start up? If it does not, chances are good that you have a small crack in a vacuum line that only gets exposed as the engine temps rise and the rubber expands a little..causing your issues.