Are you getting a CEL? My symptoms were a flickering CEL, rough idle, and code 1223 (after stomp test). I switched out the CTS (#8) and the issue went away. It returned, however, and I traced my issue to exposed wire (sheathing looked to have been rubbed away) in the lead from the CTS, maybe 3 inches from the connection at the cylinder head. The wire was shorting/arcing and this caused the flickering CEL and crappy idle, I temporarily fixed the isuue by wrapping with electrical tape and all is well for now. Long story short, if you are not getting a CEL I would strongly suspect a vacuum issue that is some how only showing itself when things are gettting warmed up in the engine bay.