I had this happening a lot until I hit the track. After about 30 minutes, or so, on the track. The PCM started to get things in order, and this issue went away. It gets better over time. Cant wait to find out what the ECU is actually doing.

 

CharlesJ is this some insider info you know about and is this a known fact?
I mean it could be true. Cause it does seem like it.

Im now pass the 2k and starting to push the car alot more, and notice the the high rpm sputter is gone!. Its sure does seem like the ECU self adjusting, and havent had the erratic idle issue for over a week now.

 

update:
I went to mitsubishi about it and explained what was happening and brought in a print out of what everyone said here in the forum. The techs said they will call hq and find out exactly what's what and get back to me asap.
That was late friday, so I imagine monday I should have an answer.
-Dave

 

+1 for studdering and wonky idle surging occasionally, hopefully my ECU figures itself out pretty soon