09 Edge, rough idle mainly at stop light with foot on brake. Less in neutral. Many tune up items done to this car, in list. 170k, regular oil changes, clean valve train (no sludge), has improved but still an issue. Have not checked vacuum reading yet, what is a good tap for this motor? May be missing something but this is most of it.
-new motorcraft platinum fire wire plugs
-all new 02 sensors reading voltage.
-new right valve cover gasket
-cleaned throttle body very well, re indexed with reset
-cleaned maf new gasket, age
-new upper intake gaskets
-clean air filter
-no codes but registers dacs if a wire is diconnected
-very smooth on highway, no bogs or performance issues under load
-similar to another issue mentioned by someone where the idle seems fine at about 400 rpm above the lowest resting idle (they where thinking of even doing a custom aftermarket program ((may or may not be a good idea))
-evap purge valve seened closed, check by self, did not have full on vacuum pump to check it, cannot generate that much vacuum but seemed like no air got past, did not want to throw parts at it
-brake booster was replaced, did not see any vacuum hose issues with plumbing when looking at it, had various things apart
-pulled 4 injector wires when looking at it, drastically changes idle, cannot get to other 2
-stated running higher end fuel injector cleaner, proper ratio with 20 gallons of gas